Size windows before positioning them.

By sizing first we can tell where the window needs to be positioned (i.e., if
the position needs to be modified to make the focused window be on screen). This
prevents flickering that would occur when we would position the focused window
off screen, check to see if it was off screen, and then move it back on
screen. Now we size it, check if it _would_ be off screen, and position it
appropriately.

Closes #101
Merge pull request #147 from leonardt/master

Focus window after movement to bring mouse with window
Adding support Cmd2+Space to cycle layouts backwards
Add some better error handling for JSON errors on .amethyst files

Closes #112
Merge pull request #148 from leonardt/master

Adding support Cmd2+Space to cycle layouts backwards
Use the old key for cycle layout forward
Add new cycle layout backwards command to README
Add widescreen tall layout

Closes #68
Merge branch 'widescreen-tall-layout'

* widescreen-tall-layout:
  Add widescreen tall layout
Set frame instead of position in layouts

This gets us the safety that setting frame performs, like setting attributes
multiple times to get around bugs in accessibility
Fix a dumb typo.
Fix command reference for default.amethyst
Update Silica to fix bug in focusing windows with sheets
Add an option for disabling the layout HUD.
Add Layout HUD option to README
Merge remote-tracking branch 'upstream/master'

Conflicts:
	Amethyst/AMConfiguration.h
	Amethyst/AMConfiguration.m
	Amethyst/default.amethyst