Explain capital letters in keystrokes
Link to relevant docs in keymap.cson file
Use shift in the example rather than explaining the difference
Add MimeType text/plain to .desktop file

This adds Atom in open with menu in KDE (possibly other DE's) for text files therefore providing better integration.
Merge pull request #3468 from atom/iz-update-keymap-instructions

Explain capital letters in keystrokes in default keymap.cson comments
Upgrade to language-xml@0.20
Merge pull request #3472 from pinak222/master

:penguin: Add MimeType text/plain to .desktop file
:penguin: Add Category 'Development' to linux desktop file

Closes #2827
Closes #3482
Closes #3488
Add initial browser process startup benchmark
Remove unused requires from main.coffee
Properly delete socket file in benchmark
Make browser process benchmark executable
Defer requiring CoffeeScript

Requiring it up front adds about 30-40ms to startup.
CoffeeScript.compile returns a string
Require https on a next tick

This require is heavy in node for some reason so only
require it on Windows since it is only used there and only
after a next tick so that it doesn't affect startup
Use fs instead of fs-plus

Since only an is file check is performed fs is sufficient
Defer ContextMenu require until requested
Remove require that is now inlined where used
:lipstick:
Require dialog when used