Implement filtering options for date & time types

[kgodey]

Problem

• We need to ensure that records that include columns of all Date & Time types support the following filters via API:
  • between {x} and {y}
  • is {x}
  • is not {x}
  • before {x}
  • after {x}
  • on or before {x}
  • or or after {x}
  • is empty
  • is not empty
• We need to also ensure that values of the filters don't have to be an exact date. We should accept natural language like "next month", or "tomorrow".
  • We could use https://dateparser.readthedocs.io/

This involves:

• Implementing the filters in the backend
• Updating the /api/v0/databases/<id>/types/ endpoint to store available filters on this type
  • Filter information should include the number of parameters needing to be passed in (e.g. between needs 2 parameters, is empty needs 0)

Additional context

• We're using our fork of sqlalchemy-filters to provide filtering. See: https://github.com/centerofci/sqlalchemy-filters.
• This issue is blocked by implementation of Date & Time types:
  • Handle TIMESTAMP data type in the backend #424
  • Handle DATE data type in the backend #425
  • Handle TIME data type in the backend #426
• Update filtering issues to cover storing filter/group information in the backend. #557 provides some context on storing filters.

[dmos62]

A brief survey on Matrix suggests that we don't need time x is before time y phrasing and can do with time x is lesser than time y. This simplifies implementation, since under-the-hood we're using a simple x < y comparison. An alternative would have been to make up a mechanism for providing filter name aliases for when parameters match some pattern (like them being time-like).

[kgodey]

Since the conversation in that Matrix channel has moved on, I'll comment here.

@dmos62 I think "21 January is less than 4 February" is not as intuitive for non-technical users, people don't regularly say that in English. I'd like to stick to the original phrasing.

[dmos62]

Ok, I'll set up filter name aliases in a dedicated PR.