Merge vim and vimrc Android.mk in a single file

Set a fallback for $VIMRUNTIME env var,
if not set, syntax.vim could be not loaded

Disable automatic backup of files (~ suffix) on save

Add also markdown and syntax.pod, to read manuals.

Use the default colored format in build process
for runtime files :
Install: /cm11/out/target/product/bacon/...

Change-Id: I45f8af834f2bee28962d120f94580fc47193adc4