- fixes about a dozen CVEs
- tweak curl-7.26.0_win-proxy.patch:
  there is a "checksrc" thing now in curl that fails the build with:
    warning: use of strtok is banned (BANNEDFUNC)
  so use strtok_s instead (which is MSVC's name for standard strtok_r)
- use Makefile.vc12 instead of Makefile.vc10
- remove strequal.obj from Makefile.vc12, it does not actually exist

Change-Id: Ie2da64980d88c72b0c902376ffc01abf97a7bc91
Reviewed-on: https://gerrit.libreoffice.org/30484Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Michael Stahl <mstahl@redhat.com>