core/Makefile: avoid exceeding MAX_ARG_STRLEN

The current method of generating the apkcerts file can fail with
a "make: execvp: /bin/bash: Argument list too long" when the path
to the toplevel directory is long enough.

In my case, the MAX_ARG_STRLEN of 131072 was exceeded with a toplevel
directory length of 52 (with 427 apkcerts).

This reduces the length of the command-line string generated by not
repeating the output path for each entry (it cd's there first).

Change-Id: I9739f9aefdf5e0febed66517c7b418a4041f49f6
build-with-colors: moar colors

- rename CL_PFX and CL_INS to better match the
  colors they show.
- add more colors.

Output of:
- most host stuff is yellow
- most target stuff is green
- installing/copying files is cyan
- import/export includes and notice files is cyan
- bootimage/recoveryimage is cyan
- and some more colors in many places ;)

Change-Id: I5532afa4ba608e0a7c408516dc9f912f9ca389f7

Conflicts:
	core/Makefile

Conflicts:
	core/Makefile
	core/tasks/apicheck.mk