Stop try to lex for matching braces in interpolation if the token_re matches an empty string. This fixes the infinite loop triggered by the test suite as a result of the change to Python 2.7 describe in http://bugs.python.org/issue16152 and reported in http://genshi.edgewall.org/ticket/540.

exclude doc/2000ft.graffle
recursive-exclude doc/logo.lineform *
include doc/api/*.*
include doc/*.html
include fixes/*.*
recursive-include genshi/template/tests/templates *.html *.txt