Describe supported Tarantool versions with limitations

For those who interested to dig to a topic himself I recommend to start
with:
- search using of helper functions like utils.tarantool_supports_* in
source code base
- search conditions with `_TARANTOOL` in source codebase
- supported Tarantool versions by tuple-keydef module [1]
- supported Tarantool versions by tuple-merger module [2]
- source code for compatibility layer in CRUD
- "Select: support jsonpath indexes (#158)" (27d825f)
- JSON paths support in Tarantool [3]
- release notes

1. https://github.com/tarantool/tuple-keydef#compatibility
2. https://github.com/tarantool/tuple-merger#backward-and-forward-compatibility-guarantees
3. https://www.tarantool.io/en/doc/latest/reference/reference_lua/json_paths/
4. https://www.tarantool.io/en/doc/latest/release/

Author: ligurio

README.md

@@ -8,6 +8,100 @@ The `CRUD` module allows to perform CRUD operations on the cluster.
 It also provides the `crud-storage` role for
 [Tarantool Cartridge](https://github.com/tarantool/cartridge).
 
+# Supported Tarantool versions
+
+CRUD depends on Tarantool features like key_def, merger, UUID modules and JSON
+paths support. We do our best to provide uniform support for all supported
+Tarantool version with help of compatibility layer, runtime feature detection
+etc. but anyway some Tarantool versions has limited support in CRUD. Please
+consult with a list below to choose a Tarantool version compatible with CRUD
+module before use:
+
+- 1.10: since 1.10.7-91-g9ee14eca5 with tuple-merger and tuple-keydef modules
+  and without UUID keys comparison
+- 2.2: since 2.2.0-268-gc7915eccd with key_def and merger modules  and without
+  UUID keys comparison
+- 2.3: since 2.3.2-99-g487289ad2 with key_def and merger modules and without
+  UUID keys comparison
+- 2.5: since 2.5.0-275-g9be50ae74 with key_def and merger modules
+- 2.6: since 2.6.2-99-gf92b9e21
+- 2.7: since 2.7.1-102-g84edc33fb
+- 2.8: since 2.8.0-113-gb3d4648d8
+
+For more information see the table below that describes Tarantool's versions
+and features for what CRUD module depends on:
+
+| Branch | merger                           | tuple-merger         | key_def      | tuple-keydef         | UUID         | JSON paths            |
+|--------|----------------------------------|----------------------|--------------|----------------------|--------------|-----------------------|
+| 1.10   | Unsupported                      | 1.10.7-91-g9ee14eca5 | Unsupported  | 1.10.7-85-g840c13293 | Unsupported  | Unsupported           |
+| 2.2    | 2.2.0-268-gc7915eccd             | Unsupported          | All versions | Unsupported          | Unsupported  | Unsupported           |
+| 2.3    | 2.3.2-99-g487289ad2<sup>1</sup>  | Unsupported          | All version  | Unsupported          | Unsupported  | Unsupported           |
+| 2.5    | 2.5.0-275-g9be50ae74<sup>1</sup> | 2.5.1-150-g98ff9aae0 | All version  | 2.5.1-145-geea90d7ce | All versions | Unsupported           |
+| 2.6    | All versions                     | 2.6.0-193-g3dc6a76c8 | All version  | 2.6.0-188-g4a12985f1 | All versions | 2.6.2-99-gf92b9e21    |
+| 2.7    | All versions                     | All versions         | All version  | All versions         | All versions | 2.7.1-102-g84edc33fb  |
+| 2.8    | All versions                     | All versions         | All version  | All versions         | All versions | 2.8.0-113-gb3d4648d8  |
+
+1. Due to Tarantool's SEGFAULT, see
+https://github.com/tarantool/tarantool/issues/4954. For Tarantool versions
+higher 2.x and lower 2.3.3 CRUD uses another implementation of select module,
+see `crud/select/compat/select_old.lua`.
+
+<!--
+- 1.10
+  - tuple-keydef: since 1.10.7-85-g840c13293
+  - tuple-merger: since 1.10.7-91-g9ee14eca5
+  - key_def: since 2.2.0-255-g22db9c264
+  - merger: TODO
+  - JSON paths: since 1.10.0-132-g658c8d852
+  - UUID: TODO
+- 2.2
+  - tuple-keydef: unsupported
+  - tuple-merger: unsupported
+  - key_def: introduced in 2.2.0-255-g22db9c264, but use is blocked till 2.2.2
+    due to https://github.com/tarantool/tarantool/issues/3398
+  - merger: TODO
+  - JSON paths: TODO
+  - UUID: TODO
+- 2.3
+  - tuple-keydef: unsupported
+  - tuple-merger: unsupported
+  - key_def: since 2.2.0-255-g22db9c264
+  - merger: since 2.3.3 due to Tarantool's SEGFAULT, see
+    https://github.com/tarantool/tarantool/issues/4954. For Tarantool versions
+    higher 2.x and lower 2.3.3 CRUD uses another implementation of select
+    module, see `crud/select/compat/select_old.lua`.
+  - JSON paths: TODO
+  - UUID: TODO
+- 2.5
+  - tuple-keydef: since 2.5.1-145-geea90d7ce
+  - tuple-merger: since 2.5.1-150-g98ff9aae0
+  - key_def: since 2.2.0-255-g22db9c264
+  - merger: TODO
+  - JSON paths: TODO
+  - UUID: TODO
+- 2.6
+  - tuple-keydef: since 2.6.0-188-g4a12985f1
+  - tuple-merger: since 2.6.0-193-g3dc6a76c8
+  - key_def: since 2.2.0-255-g22db9c264
+  - merger: TODO
+  - JSON paths: since 2.6.3 (according to comment in CRUD source code)
+  - UUID: TODO
+- 2.7
+  - tuple-keydef: all versions
+  - tuple-merger: all versions
+  - key_def: since 2.2.0-255-g22db9c264
+  - merger: TODO
+  - JSON paths: since 2.7.2 (according to comment in CRUD source code)
+  - UUID: TODO
+- 2.8
+  - tuple-keydef: all versions
+  - tuple-merger: all versions
+  - key_def: since 2.2.0-255-g22db9c264
+  - merger: TODO
+  - JSON paths: since 2.8.1 (according to comment in CRUD source code)
+  - UUID: TODO
+-->
+
 ## API
 
 The CRUD operations should be called from router.