Fixed symbols/shifted numbers in windows/linux
Update tests for new behavior
Use invalid key-code to get correct behavior in test
Response to code review by kevinsawicki
Moved translation table to dictionary.  Clarified spec.
Merge branch 'master' of git://github.com/jacobgardner/atom-keymap into jacobgardner-master

Conflicts:
	src/helpers.coffee
Merge pull-request #19