* Added version number to ApplicationSettings
* Added SettingsMigrator for defining migration rules for different ApplicationSettings versions
* Migrate ApplicationSettings when loading
* added option to define the amount of parallel indexers in the appsettings
* fixed unparsed files query in ASTVisitor
* fixed: to update a node's type in the storage the node does not have to be defined anymore
- moved LicenseChecker from App to Lib project
- added MessageDispatchWhenLicenseValid. This message takes another message as an argument which is dispatched once the LicenseChecher confirms the current license key or (if the key is invalid) once the user entered a valid key. This message is used when messages are sent that should not be working when no license key has been entered (LoadProject or ActivateTokenLocation via the IDE communication).
- added MessageShowStartScreen which makes the MainView display this screen. This message is also sent via the MessageDispatchWhenLicenseValid.
- removed startup project from appsettings.