* Fix NERDTree opening with the wrong size.
There were two commands that seemed to be causing the NERDTree window to
open in exactly half the screen width. They are:
- silent! execute 'edit ' . t:NERDTreeBufName in _createTreeWin()
- setlocal nobuflisted in _setCommonBufOptions()
These commands were reseting the width of NERDTree. The solution I chose
was to resize the window after creating the new window, and then to set
winfixwidth before setting the other common buffer options.
* Update change log and version number.
* Update CHANGELOG and change it to Markdown format.
* Add PR template with checklist for advancing the version number.
* Update version number.
* Change PR number in change log and PR template.
