add backbone-shortcuts JS library

add functionnality to add support for keyboard shortcuts from the
keymaster.js library within view
see : http://bry4n.github.com/backbone-shortcuts
provide shortcuts for editor

use backbone.shortcuts to provide shortcuts for the editor view : '#'
for tag, etc.
change shortcuts dectection library: Mousetrap.js

the Mousetrap library have some more funtionnalities so I switch to it
clean code after change Keymaster.js to Mousetrape.js
functionnal completion of tags

using a proxy on the tab-content view is not necessary anymore to know
if we are typing into a tag
first try to add shortcut to tag subview

doesn't work, no events for the shortcuts are triggered
shortcuts on tag subview work

place class 'mousetrap' on tag input to change the default behavior
need to make work the global mousetrap extension (2nt time this problem
occure)
some problem with 'enter' on FF, 'return' and 'enter' have triggered the
same event, it's strange
cleaning keydown declaration

don't work but on is way
merge with dev branch

commit e44dc4418a04224e6ce569132ee7b2dbbbaac88c
refining shortcuts for tag generation
merge with dev branch

merge with commit cc22d7e42f39f34a72d55705d47841899208af2c
generating tag by shortcuts works

but over events on tags don't work
separating in files keyboard events by languages

need to write/choose the logic for returning by the server the best file
matching the accept language of the resquest
selection of the keyboards event by language

the server serve the file with the best match against the
"accept-language" header of the request
correct saving note when we save tag
safer reset and test of number of edit for saving note
generating tag with events further simplified

- put off contentEditable on <span> for tag, <input> is enough
- when creating a tag, use dispatcheEvent() to have events on the
element for the tag after its have been inserted in the DOM

Problems :
- keyboard events of tag are trigerred by keystrokes in the general
content <section>
- the caret doesn't move to the void element
minor spec change
merging with feature.shortcuts
Embedded tags not working yet.