Update plugin_transmission.py

As of transmissionrpc-0.11-py2.7.egg/client.py
add() & add_uri() are deprecated.

Althought, I was getting transmissionError (Query failed with result:...) when trying to launch a new torrent. So I went in the rpc/client code and used the same syntax they use to base64 the data and everything'sback to normal working order ^^

Althought I suspect that line 339 (for id in r.keys(): ) won't work with the return from cli.add_torrent(), I'm not equipped to deal with that (don't know when it occurs)
Fix archive plugin handling of task aborts
Catch socket errors
Catch render errors.
Need to import the error class first.
Tests for prefer_specials

Will ensure prefer_specials is being obeyed correctly.
Support for prefer_specials in SeriesParser

If prefer_specials is True, an entry matching both a normal id type
and special will be flagged as a special. If false, entry will be
flagged as the normal id type.

E.g.: title: the show s03e04 special
prefer_specials = True -> series_id_type: special
prefer_specials = False -> series_id_type: ep
Add prefer_series support to series

Series now accepts an option 'prefer_specials'. If true, entries in
that series which parse as both a normal id type (ep, etc) and a
special will be flagged as specials. If false, they will be flagged as
the normal id type.
prefer_specials support for configure_series

Also allows plugin to accept list of special_ids
List available levels in --loglevel output

Fixes http://flexget.com/ticket/2421
Make some help text a little more dynamic
Rejected command

Rejected command, functions the same as failed. Allows rejected
entries to be listed or cleared.
Reinforce this is only remember_rejected

Remind users that only rejections known by remember_rejected are
listed or cleared.
assume_special support for SeriesParser

Flag which, if true, causes any entries with no IDs found to be
flagged as specials.
Add assume_special support to series

Series now accepts option 'assume_special'. If true, will cause any
entries with no IDs found to be flagged and processed as specials.
Also adds support to configure_series and fixes a typo in
configure_series.
Tests for assume_special
configure_series now sets series options based on the series plugin schema
Add --debug-warnings cli flag to raise warnings to errors
Catch raised warnings and print traceback without exiting
Raise all warnings in unit tests
Better debug info for @internet decorator