Add link to Google+ page to README
Add contribution guidelines
Slightly improve contribution guidelines
Fix website URL in README
Make Web API use HTTPS by default
Strip number suffixes from join date in SteamId

Closes koraktor/steam-condenser#215
Update powermock dependencies to 1.5.1
Update commons-compress dependency to 1.5
Update httpclient dependency to 4.2.5
Version bump to 1.3.5
Merge branch '1.3-stable'
Use the correct port for GoldSrc master servers

See koraktor/steam-condenser#218
Fixed Web API calls without key

See koraktor/steam-condenser#219
Implemented WebApi.getInterfaces()
DRYed up Web API tests
Add test for Web API without key
Updated logging to use slf4j and log4j

See koraktor/steam-condenser#182
Do not depend on slf4j-log4j directly

As a library, we should leave the decision for a logging framework to
the application developer.
Add a README note on logging
Merge branch 'issue-182'