v0.31.1

What's Changed

• MAINT: One test file per rule; SIM905: ignore split() with arguments by @MartinThoma in #213
• MAINT: Refactor rule registry by @MartinThoma in #214
• MAINT: Remove legacy constants and dead compatibility code by @MartinThoma in #215
• MAINT: Replace mypy wrapper classes with typed node-relation helpers by @MartinThoma in #216
• MAINT: Make the if-statement rules easier to read by @MartinThoma in #217
• BUG: Fix false positives and false negatives found in code review by @MartinThoma in #218
• REL: 0.31.1 by @MartinThoma in #219

Full Changelog: v0.31.0...v0.31.1