Update libraries, fix import errors

pom.xml

src/main/scala/de/tobias/playpad/server/PlayPadServer.scala

...main/scala/de/tobias/playpad/server/account/Session.scala

...obias/playpad/server/json/DurationSerializerHandler.scala

.../scala/de/tobias/playpad/server/json/JsonSerializer.scala

...de/tobias/playpad/server/json/UUIDSerializerHandler.scala

src/main/scala/de/tobias/playpad/server/project/Design.scala

src/main/scala/de/tobias/playpad/server/project/Pad.scala

src/main/scala/de/tobias/playpad/server/project/Page.scala

src/main/scala/de/tobias/playpad/server/project/Path.scala

...main/scala/de/tobias/playpad/server/project/Project.scala

...bias/playpad/server/project/loader/sql/DesignLoader.scala

.../tobias/playpad/server/project/loader/sql/PadLoader.scala

...tobias/playpad/server/project/loader/sql/PageLoader.scala

...tobias/playpad/server/project/loader/sql/PathLoader.scala

...ias/playpad/server/project/loader/sql/ProjectLoader.scala

...tobias/playpad/server/project/saver/sql/DesignSaver.scala

...de/tobias/playpad/server/project/saver/sql/PadSaver.scala

...e/tobias/playpad/server/project/saver/sql/PageSaver.scala

...e/tobias/playpad/server/project/saver/sql/PathSaver.scala