Build even UG obj files in tools/ subdirectory if make called there
(because color_out.o builds differently for `convert` and `uv` not to be
used interchangeably).
- supported also out-of-tree build when SRCDIR was passed, eg.:
mkdir build && cd build
make -f ../tools/Makefile SRCDIR=.. convert
+ decklink_temperature to gitignore
- moved macros to utils/macros.h (not config_common.h that is not going
to be included) and include in config_common.h the macros.h file
instead (later it should be removed)
- avoid dependency of color_out.o on host.o if build outside UG (easiest
for now)
- compile tools with '-g' (obviously for better debuggability)
