Added some notes about leak detection in unit-tests/Makefile.am
Added some notes about leak detection in unit-tests/Makefile.am

I also changed how two of the tests are built, so they link with
the static archive since this seems to cause the linker to choose
the locally-built library (where linking dynamically did not).

OPENDAP/libdap4,OPENDAP/libdap4,OPENDAP/libdap4,OPENDAP/libdap4,OPENDAP/libdap4,OPENDAP/libdap4