Fix remaining compile-fail tests

[oli-obk]

• compile-fail/match_char2.rs
• compile-fail/memleak.rs
• compile-fail/memleak_rc.rs
• compile-fail/overflowing-rsh-2.rs
• compile-fail/static_memory_modification.rs

[RalfJung]

I am seeing 11 failures, not 5:

failures:
    [compile-fail] compile-fail/deallocate-bad-alignment.rs
    [compile-fail] compile-fail/deallocate-bad-size.rs
    [compile-fail] compile-fail/deallocate-twice.rs
    [compile-fail] compile-fail/match_char.rs
    [compile-fail] compile-fail/memleak.rs
    [compile-fail] compile-fail/memleak_rc.rs
    [compile-fail] compile-fail/overflowing-rsh-2.rs
    [compile-fail] compile-fail/reallocate-bad-size.rs
    [compile-fail] compile-fail/reallocate-change-alloc.rs
    [compile-fail] compile-fail/reallocate-dangling.rs
    [compile-fail] compile-fail/static_memory_modification.rs

[RalfJung]

#395 fixes most of them except for

• compile-fail/match_char.rs
• compile-fail/memleak.rs
• compile-fail/memleak_rc.rs
• compile-fail/static_memory_modification.rs

@oli-obk Why did we stop complaining about writes to static, and out-of-range char (but not bool)?

[oli-obk]

A bunch of refactorings. I'll reintroduce it properly once the sanity check PR is merged

[RalfJung]

I opened #439 specifically for memory leaks.

[RalfJung]

I have allowed myself to change the char test in the list; compile-fail/match_char2.rs is reasonable to reject in the current state whereas match_char requires a proper implementation of an all-value validity check.