1.14.0 Jul 23 2016

- Make the session manager pluggable and replaceable. RiveScript still uses

an in-memory store for user variables, but this can be swapped out with a

replacement that puts user variables somewhere else, like Redis or MySQL.

The constructor accepts a `session_manager` parameter to use your own

session manager based on the `rivescript.sessions.SessionManager` class.

- Make the RiveScript Parser module (`rivescript.parser`) more developer

friendly by removing the parent RiveScript module as a dependency. The

parser can be used as a stand-alone module if all you want to do is parse

and validate RiveScript code.

- The `log` parameter to the constructor may now be an already opened file

handle (opened in write or append mode) instead of a string, if you already

have a file handle ready.

- Add two examples to the `eg` directory:

- `eg/sessions` replaces the in-memory session store with one that uses

a Redis cache instead.

- `eg/parser` shows how to use the RiveScript Parser module.

- Fix a bug where atomic triggers that contain a `{weight}` tag were unable

to be matched properly.

- Reorganize the unit tests into many smaller files instead of one large one.