RevBy:    tba
Details:  - as on windows some git commands take much longer it happens fairly often, that git timeouts.
          - added a timeout value to the option to let the user choose maximum timeout value (minimum is 10 seconds, maximum 5 minutes)

replace ExtensionSystem::PluginManager::instance()->getObject<Core::ICore>() by Core::ICore::instance()

forward declaration is sufficient.

Details: Refactor the git command to be able to run a batch. Run diff and diff --cached in a batch