RFR: JDK-8139653: Freetype bundled on macosx, but not correctly linked

[Erik Joelsson]

When building macosx openjdk and enabling bundling of freetype (which is 
usually not the default), the makefiles will copy the library in, but 
libfontmanager will not be able to link to it at runtime. This is caused 
by a peculiarity on macosx where a library that is being linked to 
specifies the rpath to use in any library that links to it. At Oracle we 
currently link to the libfreetype in x11 from Quartz, which is located 
in /opt/X11/lib/libfreetype.6.dylib, so the libfontmanager we build will 
only look in that location at runtime.

This patch adds a new build step, using the install_name_tool which can 
rewrite this rpath to where you actually have a dependency on your 
system. In this case right next to libfontmanager in the same directory. 
I also changed the import logic that copies in libfreetype so that it 
doesn't a .6 at the end on macosx.

This patch does not change the defaults for bundling of freetype, nor 
does it change how Oracle bundles freetype. That may come later.

Bug: https://bugs.openjdk.java.net/browse/JDK-8139653

Webrev: http://cr.openjdk.java.net/~erikj/8139653/webrev.01/

/Erik