build: use the system's ccache by default

ccache 3.x supports direct mode (http://ccache.samba.org/manual.html#_the_direct_mode)
This is not supported in the prebuilt version. Direct mode has been shown to decrease build time by up to 40x, compared to preprocessor mode used in ccache 2.4, which is substantially less

Change-Id: I224de8e5bc53bbe18a7a02fc811324307cf3ab8c
build: no longer build emulator by default

This is just increasing build times when most people are not using it.
Let's speed up builds a bit.

Building emulator should still be possible by appending BUILD_EMULATOR=true
to the build command

Change-Id: Ibd8e2b90455bd603a691c7b95466068b6fae212a
Build: Add more Color Options

Signed-off-by: Chester Kener <Cl3Kener@gmail.com>
MAKE NOVO & MAGICBROWNIES!

PS2: It's impossible to make Lokesh happy :P
PS3: ERRRR
PS4:Fix everything

This commit is for Lokesh, I really want him to get his builds down to 18 mins. Here's rooting for ya lokesh!

To use: Run "make magicbrownies" and it will clear only the out/target/product folder, for hopefully, faster builds.

Change-Id: I6ff6ffcf7c351cf18d90ab3970b13b806bffed54

Conflicts:
	core/main.mk
Moar clean options!

appclean: clears out all apks
imgclean: clears out all img files
kernelclean: clears out all kernel stuff
systemclean: clears out all system stuff
recoveryclean: clears out all recovery stuff
rootclean: clears out all root stuff

Change-Id: I3b6d9ca53e083385cca3ae66084c5a39901b3d1b
make it dirty