Add local-config plugin.

Support per-user, per-host, and per-platform custom configuration files.
Merge pull request #252 from bobthecow/feature/local-config

Add local-config plugin.
new plugin:git-flow
move git-flow completions to completions folder
Merge pull request #248 from CodeFalling/master
bobthefish: added promt support for virtualfish
bobthefish: virtualfish: move at the front
bobthefish: virtualfish: fix superscript
bobthefish: virtualfish: change color to blue
bobthefish: virtualfish: fix typo
Merge pull request #254 from rominf/bobthefish_virtualfish
Gitignore changes
Added simple mercurial pormpt to bobthefish theme
Added bookmark support to bobthefish theme mercurial prompt
[bobthefish] Use `hg root` instead of `hg stat` for in_hg
[bobthefish] Don't break when hg/git not found
[bobthefish] Add ☿ (mercury) glyph to hg prompt

This makes it easier (possible?) to distinguish between hg and git repos at a glance.
[bobthefish] Switch git/hg priority in prompt

Add TODO to do this right :P
Revert "Gitignore changes"

This reverts commit 8b94f572f170510f8fb0e2f51a657e267dc86241.
[bobthefish] DRY: we don't need two pwd-relative-to-project funcs