Bugjar support for Python 2.6

[freakboy3742]

Via @beatthem on #8, Bugjar apparently doesn't run on Python 2.6 due to changes in the Bdb API - specifically the 'skip' parameter.

[beatthem]

also I have Tcl error "Unmatched braces" (http://bugs.python.org/issue15861) in python 2.6 Because of not escaping braces in tcl code

for example bugjar path/to/autopep8.py script_name.py

[freakboy3742]

Are you able to narrow down what Tcl identifier has the unmatched braces? It sounds like we're going to need to include some manual escaping somewhere (since this won't ever be fixed in 2.6)

[beatthem]

As I see, Bugjar breaks on inspecting this variable from autopep8.py

SHORTEN_OPERATOR_GROUPS = frozenset([
    frozenset([',']),
    frozenset(['%']),
    frozenset([',', '(', '[', '{']),
    frozenset([',', '(', '[', '{', '%', '+', '-', '*', '/', '//']),
])