Fix long-standing issue of matching wrong mug file

The pattern used to match the mug shot's filename contained a bug that
allowed the wrong mug shot file to be selected.

In lieu of the unit tests that still ough to be written, below is an
example of the problem and how the two new patterns resolve it:

    In [8]: pattern = '{}*.jpg'.format(id_)

    In [9]: pattern
    Out[9]: '1147*.jpg'

    In [10]: fnmatch.fnmatch(bad, pattern)
    Out[10]: True

    In [11]: fnmatch.fnmatch(good, pattern)
    Out[11]: True

    In [12]: bad
    Out[12]: '114779.jpg'

    In [13]: good
    Out[13]: '1147.jpg'

    In [14]: pattern_a = '{}.jpg'.format(id_)

    In [15]: pattern_b = '{}_*.jpg'.format(id_)

    In [16]: fnmatch.fnmatch(bad, pattern_a)
    Out[16]: False

    In [17]: fnmatch.fnmatch(bad, pattern_b)
    Out[17]: False

    In [18]: fnmatch.fnmatch(good, pattern_a)
    Out[18]: True

    In [19]: fnmatch.fnmatch(good, pattern_b)
    Out[19]: False