imported ARCHI DROID'S build optimizations
imported reposync function
imported some missing flags from archi's optimisations
build: Default to dtbToolCM

* The default dtbTool isn't the correct module name for the module that
  actually lives in device/qcom/common/dtbtool

Change-Id: I80b427e3652b99742573bc4d2829e51645a8822b
adjusted ccache settings for kernel
Merge branch 'kk-4.4.3' of https://github.com/Mahdi-Rom/android_build into HEAD

Conflicts:
	core/combo/arch/arm/armv7-a-neon.mk
Merge commit '244bdbc' into archi-mahdi

Conflicts:
	core/combo/TARGET_linux-arm.mk
	core/combo/arch/arm/armv7-a-neon.mk