cleanup / pep8
add a newline to tests
improvement for pickling
care for python 3 dict.items iterator return (in python2 list)
added filesystem cache options
move module caching from builtin to cache
renamed code -> source
simplify parser_cache checks
default directory for parser caches: HOME, #102
basic pickle implementation #102
pickling works now (had problems deriving str, see http://stackoverflow.com/questions/14248633/python-pickle-derived-str-object), #102
don't pickle cursor modules