League screen gets a rework, plus a batch of fixes

Changes introduced today:

• FEATURE Reworked the League screen — something that's been bugging me for a while. Introduced tabs (if this design works well for you, I'll likely extend it to more screens — feedback welcome), moved the league schedule into League where it belongs, and split leaders into two separate tabs for clarity
• FEATURE Added Q1-Q4 filters to play-by-play — proposed by @praedyn in his bug report
• FIX Improved the tactics UI to prevent technical "Invalid request" messages from showing up to users — @lordgohan
• FIX Fixed incorrect lineup display in cases of unplanned in-game replacements — @praedyn
• FIX Moved the release player button out of a spot where it was too easy to fire a player by accident — reported by @doman

Next up: started looking into injuries after several in-game reports that the system needs improvement. Fixes will land together with the medical staff feature — stay tuned.

This game is from the very beginning driven by the community. Keep delivering ideas, and together we can build the best online basketball manager ever.