1.5: Add new functionality (#9)

* Fix issues and do some changes
* change pg_configuration installation method
* remove unused task for pg_configurator
* move libpq library to Debial-like systems tasks
* change README file with appropriate commands

* Fixes:
* remove installation of packages from pip repo;
* remove python3-related packages installation;
* remove unnecessary package installation;
* fix idempotence issue wuthin RedOS OS
* add feature that allows to skip external repo connection to the system;
* change FQDN to hostnames within README and playbook tasks

* Add important information into README file; fix variable name;

* Changes:
* add update feature to all components except DBMS;
* change README file (add some additional info);
* fix issue with patroni ssl templating;

* Add proper haproxy configuration for SSL-covered patroni

* Add missing conditional check to task that upgrades patroni

* Fix jinja templating that causes issues in RedOS;

* add wal-g support

* Minor changes made:
* fix issue with pgbouncer;
* add support for astra-1.8.1 and redos-8;
* change README file with actual instructions;

* Fix package name in RHEL-based tasks

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Co-authored-by: Maxim Bagirov <[email protected]>