Make build work with and without LAZperf.
Remove debug.
Merge pull request #660 from PDAL/issues-658

Make build work with and without LAZperf.
Port of python filters (predicate and programmable) to plugins; separate
test executables
use CMakeParseArguments in PDAL_ADD_TEST
accidently deleted wrong line in macro, fix it
fix broken SupportTest and python plugin options