Sirope

Changelog:
- Adds max number of objects ot filter() and enumerate().
- Adds load_first(cls: type, n: int) and load_last(cls: type. n: int), able to load the first n object and the last n objects.

Changelog:
- Fixed the restriction on the __init__() method, by resorting to __new__,

Changelog:
- Fixes naming oddities.
- Adds find_first.

Changelog:
- Adds an enumeration method.

Changelog:
- Added Sirope.filter_by(), which accepts a callable and a class and applies the predicate to all objects of that class, returning the compliant objects.
- Added some guards so functions such as Sirope._obj_from_json() or OID.from_pair() return None instead of launching an undescriptable error messages due to null parameters.

Changelog:
- A Redis instance can be passed when creating a Sirope object, so it is possible to configure it beyond the default values. You can still pass nothing so the defaults are assumed.