Renamed NDEBUG -> SING_NDEBUG in order to avoid confusion with GCC macro
Added '--cflagswithdebug' option for *-config scripts (for more debug/asserts/checks)
Show more building flags in versionString (-v)
Fixed lib*-config scripts
Use @prefix@, @includedir@ and @libdir@ in lib*-config scripts

NOTE: user should do: configure --prefix=FIXED_PATH and make install
Added FLINT flags to lib*-config scripts
Fixed lib*-config

NOTE: libdir needs exec_prefix by default
Commented out obsolete 'initializeGMP'