Fix doc: :CommandT uses g:CommandTTraverseSCM

Original pull request:

  https://github.com/wincent/command-t/pull/140

Applied a minor tweak for clarity (ie. mention "current project" before
referring to the potentially confusing `g:CommandTTraverseSCM` setting).

Signed-off-by: Greg Hurrell <greg@hurrell.net>
doc: Update HISTORY section with reference to Daniel Hahler's patch
Merge branch 'blueyed/fix-doc-pwd' into next

* blueyed/fix-doc-pwd:
  doc: Update HISTORY section with reference to Daniel Hahler's patch
  Fix doc: :CommandT uses g:CommandTTraverseSCM