added git-locked to check what files have been locked
Merge pull request #270 from kevinawoo/hotfix/git-locked

git-locked
changing incorrect reference of tag to tags
replace visionmedia/git-extras to tj/git-extras

Although Github reserves the 'visionmedia' user space(a visit to there
will be redirected to 'tj'), it's better to
rename the links from visionmedia/git-extras to tj/git-extras
correct the '-m' argument for grep. Then regenralize git-extra

'-m' option is supported both in GNU grep and in BSD grep
GNU grep: <http://linux.die.net/man/1/grep>
BSD grep:
<https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man1/grep.1.html>
correct the format of git-rebase-patch.md. Now we can handle it with script

Also regeneralize all markdown documents.
Merge pull request #272 from spacewander/master

replace visionmedia/git-extras to tj/git-extras
Merge pull request #271 from bohnman/git-rename-tag-fix

tag to tags
add new command 'git root' to show the path to root of repo
Merge pull request #273 from spacewander/master

'git root' shows the path to root of repo.
Update `mktemp` command to work on Mac OS X

Fix issue 274. It seens like the same with
[this issue](https://github.com/StanAngeloff/lotte/issues/1).
modify the behavior of git-ignore, now it will cd root to find .gitignore
Merge pull request #275 from spacewander/master

Update `mktemp` command to work on Mac OS X.
Version 2.2.0
Updated the list.
Version bump.
Merge pull request #276 from spacewander/master

git-ignore will cd root to find .gitignore.
Fixes #277
Merge pull request #278 from tj/delete-submodule-fix

Fixes #277.
git-info: POSIX compliance

Replace `echo -n` (non-POSIX) with an helper function `echon` echoing a
newline after given expression.