Relocate issues/issue-51022.rs to
entry-point/main-with-lifetime-param.rs
Relocate issue-50714.rs to entry-point/main-where-fn-bound.rs
Rename issue-118772.rs to main-with-invalid-signature.rs and delete
duplicate test
remove ui/entry-point/issue-118772.rs in issues.txt
Relocate fn-main/wrong-location.rs to entry-point/main-in-submodule.rs
Remove fn-main directory
Relocate issue-50688.rs to mismatched_types/array-len-is-closure.rs
This function is now used to check `#[panic_handler]`, `start` lang item, `main`, `#[start]` and intrinsic functions.
The diagnosis produced are now closer to the ones produced by trait/impl method signature mismatch.
