Start installing GRE libraries & components into a separate dist/gre directory as part of the default build.

Bug #186241 r=dougt

docshell/shistory/public/Makefile.in

@@ -27,6 +27,7 @@ VPATH		= @srcdir@
 include $(DEPTH)/config/autoconf.mk
 
 MODULE		= shistory
+GRE_MODULE	= 1
 
 SDK_XPIDLSRCS   = \
                   nsIHistoryEntry.idl \

docshell/shistory/src/Makefile.in

@@ -31,6 +31,8 @@ LIBRARY_NAME	= shistory
 EXPORT_LIBRARY = 1
 IS_COMPONENT	= 1
 MODULE_NAME	= Session_History_Module
+GRE_MODULE	= 1
+
 REQUIRES	= xpcom \
 		  string \
 		  necko \