bug in youtrack python client library. gcode->youtrack

Hi guys, i found a small bug in the library and I don't know if there's a better place to report it, so i will do it here.

When the issues are searched by gdata, a ProjectHostingClient is created but the loggin never happens. So later, when the query run, it's runs as a visitor, and the problem I had was emails address hidden from google (like: hugo....@gmail.com).

So, it's really easy to fix, just add this line:

source.client_login(source_login, source_password, source='youtrack', service='code')

between lines 252 and 254.