Add vi-tilde-fringe extension
Update screenshot
Add magit-gitflow and fix the `f` issue for feature

The solution to fix the `f` binding issue is to not
alter emacs-state-map. By keeping emacs map untouched
we have a fallback for modes like magit-gitflow which
require the `f` key.

Indeed with the current implementation of the `fd`
sequence it is not possible to guess what the `f` key
must do for a given mode. The only solution for now is
to keep one not modified state map (emacs is a good candidate
for this).
vi-tilde-fringe is now available in MELPA

Also hide the lighter.
Add screenshot of spacemacs in urxvt
Add terminal screenshot in readme
Add git-flow instruction for contributions in readme
Set `C-u` to scroll-up and `<SPC> u` to universal-argument
Update old name of submodules in .gitmodules
Lazy loading of tern-auto-complete
Lazy loading of helm
Fixes #46 Weird behavior of projectile

Projectile takes time to load (around 0.2 seconds) and it is
lazy loading friendly if we want to enable it globally.

To be able to lazy load it, we encapsulate the binded calls
in spacemacs/xxx functions which take care of firing the
mode globally if required.
Correctly load helm bindings at initialization time

instead of at loading time which is useless :-)
Fix helm-show-kill-ring binding
Fix helm lazy loading for describe-xxx functions
Add bindings for describe functions
Add notes about master and develop branches in install section
Remove obsolete readme section
Use projectile-commander and bind it to `<SPC> p p`
Fix ido-vertical key bindings stability

Sometimes the spacemacs key bindings for ido-vertical did not work.