added Flickr drop-in

The Flickr drop-in uses oauthlib directly for OAuth1 operations
Flickr: clean up based on suggestions
Merge pull request #4 from kylewm/flickr

added Flickr drop-in
comment: flickr doesn't support oauth declines
no drop shadows on dropbox or flickr logos
gitignore flickr api key files
switch twitter from /authorize to /authenticate to avoid prompting every time

fixes snarfed/bridgy#245
background: https://dev.twitter.com/discussions/1253
update tweepy, port to requests_oauthlib

tweepy itself ported to requests_oauthlib in tweepy/tweepy@416d0d680b9690b4615c21dd0037efb5f95c906c
revert part of d08c4d5. keep twitter_auth.signed_urlopen() and friends
switch to my own fork of tweepy, in preparation to implement tweepy/tweepy#471
oops, fix tweepy submodule url
add support for Twitter's x_auth_access_type query param via new tweepy access_type kwarg

background:
https://github.com/tweepy/tweepy/issues/471
https://dev.twitter.com/docs/api/1/post/oauth/request_token
work around Twitter API bug: /authorize and x_auth_access_type don't play nice together
flickr: pass perms param to oauth/authorize explicitly

flickr's oauth flow sometimes breaks if it's not provided. http://stackoverflow.com/questions/6517317/flickr-api-error-when-oauth

thanks to @kylewm for helping debug!
update webutil
add Flickr to the list of OAuth1 providers
Merge pull request #5 from kylewm/patch-1

add Flickr to the list of OAuth1 providers