New bear HTTPolice breaks the build

[jayvdb]

Collecting brotlipy>=0.5.1 (from HTTPolice~=0.5.2->coala-bears==0.12.0.dev99999999999999)
  Downloading brotlipy-0.7.0.tar.gz (413kB)
    Complete output from command python setup.py egg_info:
    Package libffi was not found in the pkg-config search path.
    Perhaps you should add the directory containing `libffi.pc'
    to the PKG_CONFIG_PATH environment variable
    No package 'libffi' found
    Package libffi was not found in the pkg-config search path.
    Perhaps you should add the directory containing `libffi.pc'
    to the PKG_CONFIG_PATH environment variable

    No package 'libffi' found

    Package libffi was not found in the pkg-config search path.
    Perhaps you should add the directory containing `libffi.pc'
    to the PKG_CONFIG_PATH environment variable
    No package 'libffi' found
    Package libffi was not found in the pkg-config search path.
    Perhaps you should add the directory containing `libffi.pc'
    to the PKG_CONFIG_PATH environment variable

    No package 'libffi' found

    Package libffi was not found in the pkg-config search path.
    Perhaps you should add the directory containing `libffi.pc'
    to the PKG_CONFIG_PATH environment variable

    No package 'libffi' found

    c/_cffi_backend.c:15:17: fatal error: ffi.h: No such file or directory

     #include <ffi.h>
                     ^
    compilation terminated.

    Traceback (most recent call last):
      File "/usr/lib64/python3.4/distutils/unixccompiler.py", line 116, in _compile
        extra_postargs)
      File "/usr/lib64/python3.4/distutils/ccompiler.py", line 909, in spawn
        spawn(cmd, dry_run=self.dry_run)
      File "/usr/lib64/python3.4/distutils/spawn.py", line 36, in spawn
        _spawn_posix(cmd, search_path, dry_run=dry_run)
      File "/usr/lib64/python3.4/distutils/spawn.py", line 162, in _spawn_posix
        % (cmd, exit_status))
    distutils.errors.DistutilsExecError: command 'gcc' failed with exit status 1