[INTERNAL] add intellij.editor package

Add the ColorManager implementation, that always uses the
default colors

Change-Id: Ifa256da12f4f18a512f92bed2e32764154029302
Reviewed-on: http://saros-build.imp.fu-berlin.de/gerrit/1769
Tested-by: Jenkins CI
Reviewed-by: Holger Schmeisky <google@schmeisky.com>