init
add README
rename gitify.vim to signify.vim
improve README
add doc
unify variable naming
readme: small cosmetic change
add sanity check for empty buffers
fix color bug

Fixes a bug that happened, when an active buffer was closed and
reopened. Calls s:set_colors() in this case.
add IRC nick to docs
add screenshot
fix "removed lines" bug

The signs for removed lines were set in the wrong manner, because I used
the wrong part from the diff file. It's working correct now.
add empty line
check that synIDattr() doesn't return -1
add proper jump handling
rename 'change' to 'hunk' in the appropriate places
much more configurable colors
doc: refactor options and functions
readme: add pathogen as suggested installation method
sy should be unobtrusive; do not print messages