Add Build Colors.
-Thanks to OmniROM

Based on tpruvot/chirayudesai's commits, add some color to stdout
and but make it a little easier to customize. Colors are now mapped to
categories and can be edited in Makefile if you or your terminal's
background color do not like them. Defaults:

host stuff: yellow
target stuff: cyan
install/copy: green
filesystem/images: green
imports/exports/includes/notices: green
deletes: red
complete msg: bold green

Coloring can be disabled with "export BUILD_WITH_COLORS=0"

Conflicts:
	core/base_rules.mk
	core/dex_preopt.mk
	core/java_library.mk
	core/package.mk