Add DOCS options to ports that should have one.

Also various fixes related to said option.

PR:		230864
Submitted by:	mat
exp-runs by:	antoine

databases/py-PyGreSQL/Makefile

@@ -19,6 +19,8 @@ USE_PYTHON=	autoplist distutils
 
 PORTDOCS=	*
 
+OPTIONS_DEFINE=	DOCS
+
 post-install:
 	${STRIP_CMD} ${STAGEDIR}${PYTHONPREFIX_SITELIBDIR}/_pg.so
 	@${MKDIR} ${STAGEDIR}${DOCSDIR}