Clean up eterm code a teeny bit
Clean up PSMMetalTabStyle code style
Update TabClose buttons for Yosemite style
Update metal tab style to look like yosemite
Get rid of tab styles other than metal
Delete non-Yosemite-style tabs
Get rid of label-coloring code. Improve indicator icons.
Move tab icon to right side of label
Remove some unwanted code for disabling tab closing. Bring tab icons closer to indicator.
Use buster icon to indicate a dead session
Merge branch 'killDrawer' of https://github.com/gnachman/iTerm2 into killDrawer