Features/10 parallelize processing

[github-actions[bot]]

File	Coverage
All files	45%	:white_check_mark:
src/config.rs	37%	:white_check_mark:
src/feed.rs	32%	:white_check_mark:
src/feed_reader.rs	71%	:white_check_mark:
src/feed_utils.rs	96%	:white_check_mark:
src/import.rs	0%	:x:
src/main.rs	0%	:x:
src/message.rs	0%	:x:
src/settings.rs	29%	:white_check_mark:
src/store.rs	40%	:white_check_mark:
src/syndication.rs	50%	:white_check_mark:

Minimum allowed coverage is 10%

Generated by :monkey: cobertura-action against 491e8534bc552aed951141e753b89a133590699e

[Riduidel]

Fixes #10