[Libreoffice] support for mono 2.8

While building Go/LibO for ArchLinux I've run into a few issues today
after we had updated our mono packages to the 2.8 release.

1) the patches/mono/*.diff call mkbundle2 at several places.

"mkbundle2" (that called /usr/lib/mono/2.0/mkbundle.exe) isn't
shipped anymore in the mono 2.8 release /usr/bin. It's replacement is
"mkbundle" that calls /usr/lib/mono/4.0/mkbundle.exe though the
2.0/mkbundle.exe still exists without a script to call it from /usr/bin.

I replaced all mkbundle2 calls in the *.diffs with a sed command and
have run into

2) somehow the pkgconfig path isn't well read

/build/src/libreoffice-build-3.2.99.2/build/libreoffice-3.2.99.2/cli_ure/source/bootstrap/native_glue.cxx:75:34:
fatal error: mono/metadata/object.h: No such file or directory
compilation terminated. dmake:  Error code 1, while making
'../../unxlngx6.pro/slo/native_glue.obj'

The header is present:
/usr/include/mono-2.0/mono/metadata/object.h

current mono.pc:
prefix=${pcfiledir}/../..
exec_prefix=${pcfiledir}/../..
libdir=${prefix}/lib
includedir=${prefix}/include/mono-2.0
sysconfdir=/etc

Name: Mono
Description: Mono Runtime
Version: 2.8

Any idea why the header isn't found?

Is it a big step to make LibO compile and work with mono 2.8 or just a
few hacks to satisfy the build process for the 3.3.0 release?

-Andy