Cleanup markdown span handling, take 2#80550

Merged

bors merged 5 commits intorust-lang:masterfrom

bugadani:markdown-refactor

Jan 2, 2021

Commits on Dec 31, 2020

Use ranges returned by pulldown

bugadani
and
Joshua Nelson
committed
Remove unnecessary scope

bugadani
and
Joshua Nelson
committed
Always provide a range

bugadani
and
Joshua Nelson
committed
Collect links into a single vector
bugadani
committed

Commits on Jan 2, 2021

Only use locate for borrowed strings
bugadani
committed