Change integer fallback RFC to suggest `i32` instead of `int`.
Int fallback restoration: Clarify the default name argument
Int fallback restoration: Add case analysis
Int fallback restoration: Formatting
Int fallback restoration: Expand on the perf argument
Int fallback restoration: Remove unrelated mode change
Merge pull request #452 from tbu-/pr_inti32

Change RFC #212 (integer fallback) to use `i32` instead of `int` as the fallback