Clean up the Makefile.

Since this is C++, use the $(CXX) variable instead of redefining $(CC).
Use the more common $(CXXFLAGS) and $(LDFLAGS) insead of $(CCOPTS) and $(LDOPTS). Also add to them instead of redefining them.
Remove /usr/local/{lib,include} from flags.
Create a $(OBJS) variable automatically from the *.cpp filenames.
Use wildcards and automatic variables to greatly simplify the compile rules.