Log Message:
Add distribution patch (from gmplib.org) for the following bug:

    When using mpf_set_str, mpf_init_set_str, or mpf_inp_str
    with a base > 36, the supplied base will actually be ignored,
    and the exponent 0 will be supplanted. [2007-12-10]

All tests pass on NetBSD/amd64 4.99.58.

Bump revision.