Details:
- Updated 3m4m and mixeddt Makefiles and runme.sh scripts, mostly to
port recent changes to the former to the latter.
- Disabled (for now) code in 3m4m/test_*.c files that disables all
induced methods except for the one that is requested from the
Makefile via the IND macro. This is done because usually, we want to
test whatever method is enabled automatically for complex datatypes.
(That is, when native complex microkernels are missing, we usually
want to test performance of 1m.)