Loads of code cleanups

[rasjani]

• removed symbian & maemo specific build rules
• removed symbian & maemo specific code
• removed symbian specific files
• fix few compiler warnings on osx clang
• tabs to spaces and removal of trailing whitespaces
• gitignore updated

[rasjani]

Windows builds for this code: https://ci.appveyor.com/project/rasjani/cutedriver-agent-qt/build/23 Osx & Linux Builds: https://travis-ci.org/rasjani/cutedriver-agent_qt/builds/226724343 - not finished at the time of the writing but i except them to pass as they do locally.

[jppiiroinen]

I will check this now.