because I didn't sync PLIST-webkit (missed because it's only built as
a non-default pseudopackage); fix this by adding VERSION to SUBST_VARS
and syncing PLISTs, which also reduces the risk of problems in the future.
Several patches from the FreeBSD port.
Create -mozilla and -webkit subpackages. Do NOT build -webkit by default
because of a cyclic dependency:
libproxy,-webkit -> webkit -> libsoup -> libproxy
tested in a bulk by landry@
ok landry@