document implicit lifetime bounds
Add documentation about implicit lifetime bounds that the compiler can infer for functions, trait implementations, and structs. This draws from RFC 2093 (for structs) and RFC 1214 for functions and trait implementations.
This is built on #1062 and #1060.
It does substantially increase the length of the page it's on, so I would be open to some reorganization.
Fixes #289.
We talked about this on the lang docs call. This is good work.
There are two things that we want to change before merging this. One is that we'd like the verbiage to state the rules more directly rather than leaning so heavily on the examples. The other is that we'd like to roll this into the section on implied bounds.
@rustbot author
:umbrella: The latest upstream changes (possibly f80986bb34aa67f30bbb6b92f7b69b250e275126) made this pull request unmergeable. Please resolve the merge conflicts.