support for bearer token https://dev.twitter.com/docs/auth/application-only-auth
Merge remote-tracking branch 'bdanchilla/master' into develop
Supprt proxy

Add function setProxy($proxy_host, $proxy_port=8080, $proxy_username='', $proxy_password='')
Use proxy

if (defined("PROXY_HOST")) $connection->setProxy(PROXY_HOST, PROXY_PORT);
Merge branch 'proxy' into develop

Conflicts:
	twitteroauth/twitteroauth.php
Add proxy setting
Add setBearerToken() invalidateBearerToken()
Fix search.php