Fixed gitinfo application, now it would not spam on jist-git-init'ed
repos, fixing #1.
Also reworked checks things, now every function will call
gitinfo_internal_checks function and do nothing if internal checks
method returns 1.
* Added new app: gitinfo, for retrieving git information.
* Default (and only one for this time) prompt is now using gitinfo
app for showing git status in current directory.
