Re-added check for database connection on service startup

The service won't begin with starting if no connection to the configured database server is available, since that is crucial for the services to function.
Code cleanup and tidying

Some AssemblyInfo.cs files were not correct, some projects missed information in there, and sometimes the information was incoherent. Also some .csproj-files had maliciously formatted references, which could occassionally lead to compilation or resolving issues.