New port: devel/grantlee5 and Uses/grantlee.mk

The upcoming KDE Frameworks ports need grantlee5

• Add devel/grantlee5 and move installed headers into a subdirectory include/grantlee5
• Move header files from devel/grantlee into a subdirectory include/grantlee4 to make sure ports do not pick up the wrong headers
• Add Uses/grantlee.mk to handle the PLIST_SUB and LIB_DEEPENDS needed by ports using grantlee (before we set the PLIST_SUB manual in very of the depending ports, which now should not be needed anymore).
• The ports depending on devel/grantlee have been modified from LIB_DEPENDS=libgrantlee_gui.so:devel/grantlee to USES=grantlee:4 as this does not affect the package no version bumped was made.

Reviewed by: mat, rakuco
Approved by: rakuco (mentor)
Differential Revision: https://reviews.freebsd.org/D7434