xffm location for mcs plugin

[Jasper Huijsmans]

Hey Edscott,

Regrading bug 389 (http://bugzilla.xfce.org/show_bug.cgi?id=389) I noticed 
you had these lines in the Makefile.am:
===
#plugindir = @XFCE_MCS_MANAGER_PLUGINSDIR@
# Please do not remove this hack until 4.2 release,
# it is currently needed for development on a clean box
# based on xfce_4_0_x
plugindir = $(prefix)/lib/xfce4/mcs-plugins
===

Would it be alright to change it for RC1? After all that is supposed to be
ready for release ;-)

	Jasper