Document filtering options of user's solutions tab

[hobovsky]

https://discord.com/channels/846624424199061524/846630620444229632/857425461030420551

Filtering your solutions

You can now filter your completed solutions page by appending query parameters (no UI yet):

• language={language_id} only show solutions in language
• rank=-{kyu} only show solutions for kata with specified rank
• q={term} only show solutions containing some short term (4-20 characters, case-sensitive)
• sort=1 show the oldest first (the default is last attempted kata first)

Example

https://www.codewars.com/users/{username}/completed_solutions?language=rust&rank=-8&q=collections
shows Rust solutions for 8 kyu kata containing collections.