fixed pages test for python2/3

there were some unicode problems
simplify nowvideo code a bit
simplfiy the download_queue

the name was never used
removed some pylint error messages
simplified prog.py through putting code in more methods
small code improvements for stream (to reduce pylint warnings)
small code simplifications
smal url improviements
test resumedownload too - fixes for streamhandler
downloader: stop and remove other parts when download fails
write to flashget_log when all downloads completet
try to remove pinfo from downloader

this will make the api much easier
the downloader should only know:
        - where the resulting file gets saved
        - what is the url (or in this case the stream-class)
        - what are the parts and alternatives
removed all pinfo from downloader
remove config from downloader
removed more pinfo
fix single stream download
simplification of __init__ in urlmgr

merged the cache-related things into one
and make them a bit more configurable
urlmgr by default now only uses FileCache
added downloader tests and made it executable on it's own

for the execution I copied from web2py testcode, so the
    syspathes are set properly
hide the extension interna with an extra command

also load the extension folder not at import-time
but at calltime
simplify videoinfo class by removing not used things