Optimized, fixed and with new features!
Fixes:
1. Selecting from `SolidTable` and `MemoizedTable` instances now working with `None` values in records
2. Creating builtin `SQLTable` child-classes by method `from_database` now parse default column values (before default values was always read as strings)
3. `PrimaryKeyTable` table field now typed better
4. Logging now works properly
Optimizations:
1. Now `table.SQLTable` has special method `_execute_where(record, query, parameters, conn_kwargs)` which automatically adds `WHERE` clause to the end of the provided query to select specified record. It allows to **select records only by their primary key or unique value** if they have one of them.
2. Removed some cycles.
New features:
1. ``Parser`` class that saves all data parsers and allows to use them later in code. Automatically registers adapters and converters via sl3 functions on instantiating.
2. ``Parsable`` class that allows registrate parser via inheriting from it. Child classes must have `classmethod fromdict` and `asdict` methods. Also they may declare aliases in classvar `aliases`