* fix(help_tags): show help tags on windows (#3126)
On Windows, `builtin.help_tags` picker does not show any help tags.
To fix this, the following changes are needed:
1. `util.path_tail` checks unix separator `/` on Windows and leave the
original implementation intact on unix systems.
2. Line endings should be taken carefully on Windows. `vim.split` with
only newline `\n` character as separator may result in unexpected
crash when parsing large files. When splits on lines are needed, call
it with `\r?\n`, or even set up a wrapper function in utils is more
prefered.
Fixes#3126
* fix: handle cross platform line splits
349660c0d3