Added .gitignore file to neglect backup files
Added interfaces and entities for storage communication

 * IMessageAdapter for message reception and storage
 * IUserAdapter for user management and credential checking

 * ShoutBoxMessageEntity describes a stored message
 * UserPrivilegesEnum  describes the available user modes
Added dummy controllers
Added Index

The implementation checks for valid configuration.
If no valid configuration is found the system will
redirect to the installer.