Size check for share limits

[estebanthi]

Description

Provides two new configuration options for share_limits (include_smaller_than and include_bigger_than) to apply share limits to torrents depending on their size. The size should be in GB.

Example:

share_limits:
  large:
    priority: 10
    include_all_tags:
      - some_tag
    include_bigger_than: 48 # GB
    max_ratio: 1.0
  medium:
    priority: 11
    include_all_tags:
      - some_tag
    include_smaller_than: 48
    include_bigger_than: 10
    max_ratio: 1.0
  small:
    priority: 12
    include_all_tags:
      - some_tag
    max_ratio: 1.0

Fixes #472

Type of change

Please delete options that are not relevant.

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [x] This change requires a documentation update

Checklist:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have added or updated the docstring for new or existing methods
• [x] I have modified this PR to merge to the develop branch