remove matrix resize test program
create only one library `libsoft.la'
remove old FlexibleSUSY test classes

All of these tests are integrated into FlexibleSUSY.
remove NMSSM test programs
Revert "remove NMSSM test programs"

This reverts commit e33db8b5f8e79118c2a4628ad4cc1c3762daebff.
The NMSSM test programs are still needed for testing.
At some point one of them will be converted to a proper user
example, just like main.cpp.
Merge branch 'tidy-makefile' into nmssm2