Add some unobtrusive changes to handle sources which aren't ports (SRC_ENCAPSUATION).  Stick in some cd ${.CURDIR} directives which have been (benignly) missing all this time.  Allow more types of targets to be selectively disabled.
Add some unobtrusive changes to handle sources which aren't ports
(SRC_ENCAPSUATION).  Stick in some cd ${.CURDIR} directives which have
been (benignly) missing all this time.  Allow more types of targets to be
selectively disabled.

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase