Added task 3
Added parameterized tests
Some comments added
Removed tests
Checkstyle fix
deleteRecursievly moved to FileUtils & added some additional exception throw
Some minor fixes and situation handling
File separators in table names are now prohibited
checkstyle fix: if construction must use {}
removeTable now removes table from tableInstances map
Some classes renamed & todo's done
Wrapped IOException into RuntimeException
Moved FileMap
FileMap implements AutoClosable
Added additional exception handling
Now read-only databases allowed
charset extracted as constant
Added warned_unsaved constant
Some code rewritten in Java 8 style
Added close on exit