Upgrade MPC to version 1.0

Imported from <a href="http://trac.sagemath.org/sage_trac/ticket/13290">trac #13290</a>.

Patch for the mpc spkg, for review only

Reported by: jdemeyer

Component: packages

CC: jpflori,, zimmerma

Report Upstream: Fixed upstream, in a later stable release.

Authors: Jeroen Demeyer

Dependencies: 

Work issues: 

Reviewers: Leif Leonhardy, Volker Braun

Merged in: sage-5.3.beta2

Attachments: <ol><li><a href="http://trac.sagemath.org/sage_trac/attachment/ticket/13290/mpc-1.0.spkg-gcc-4.7.0-config.log">mpc-1.0.spkg-gcc-4.7.0-config.log: `config.log` from MPC 1.0 spkg showing use of `gcc` instead of `gmp.h`'s CC</a> by leif at 20120727T15:41:20</li><li><a href="http://trac.sagemath.org/sage_trac/attachment/ticket/13290/configure.ac.patch">configure.ac.patch: "Upstream" patch to `configure.ac` to fix `CC` not being taken from `gmp.h`.</a> by leif at 20120727T20:25:31</li><li><a href="http://trac.sagemath.org/sage_trac/attachment/ticket/13290/13290_mpc_1_0.patch">13290_mpc_1_0.patch: Patch for the Sage library</a> by jdemeyer at 20120801T14:16:12</li><li><a href="http://trac.sagemath.org/sage_trac/attachment/ticket/13290/mpc-1.0.p0.diff">mpc-1.0.p0.diff: Patch for the mpc spkg, for review only</a> by jdemeyer at 20120801T14:19:24</li></ol>