swig: bump to 2.0.12; drop all patches

Update to 2.0.12. It drops all previous patches. This release
contains

    C++11 support for new versions of erase/insert in the STL
    containers.

which is required for GCC 4.9.0/libstdc++ in C++11 mode.

Tested on slc6_amd64_gcc481 and slc6_amd64_gcc490 compiling
cmssw-tool-conf.

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>