Fixed two small typos
Merge pull request #246 from RickKuipers/patch-3

Fixed two small typos
Allow setting of custom user hydrator and user mapper from config file.

Allow setting of custom user hydrator and user mapper from config file.

Updated README.md to include the 'user_mapper_class' and 'user_hydrator_class' config options.
Extracted the creation of the User Entity into a separate ServiceManager entry, for easier overriding.