complibs/mpfr: add upstream patches

cc/gcc: add new patch, fixers building on x86 for target armeb (at least!)

Patch from Ralf Wildenhues:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41818#c5

Testing thanks to Joachim Nilsson:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41818#c7

Merge.

complibs/mpfr: add latest version 2.4.2

Note: the MPFR site happens to be down at the time I wrote
this message, and happens to be down quite often.

Once it's back up'n'runnin', I'll mirror as much as possible
the MPFR tarballs on my site, but in the meantime, you'll
have to handle it by yourself (patience...).

complibs/mpc: add latest version 0.8.1

scripts/addToolsVersion: add support for MPC

cc/gcc: add patch to fix armeb in gcc-4.4

On x86, gcc-4.4.x breaks when building for target armeb.
It is still required to configure with: --disable-shared

Note: if building on an x86_64, there is no need to pass --disable-shared

scripts/addtoolversion: prepare for hooks for tools others than gcc

The upcoming git support will require hooks for glibc as well.

scripts: protect against partially extracted source

In case of failure (eg. user hitting Ctrl-C), avoid extracting over
partially extracted source. Will help once we have git available.

scripts: handle custom or empty extension when extracting