initial take on a generic interface to cinema database stores

What we have here is a class that represents a cinema data store
and provides a few essential operations. These are:
* create from info.json,
* define exploration parameters
* define file mapping of paramters to files
* a functioning path to both read and write heavy data stored inside
* write the contents back to disk

hierarchical storage and other specializations such as composite
image storage, is missing at this point