lib: Change AllocErr to AllocError
lib: Add `Allocator.free_bytes()`
Returns the combined size of all free memory regions.
misc: Increase minimum allocation size to `size_of::<usize>() * 4`
ci: Remove appveyor and move to GitLab CI
[ci skip] Add docs.rs badge to README
Add iterator over Allocator regions
Fix recursive backwards-combining, among other things
Add recursive backwards-combining of free regions
Bump version to v0.1.0-beta.2
Add documentation to everything
Attach new regions to the tail of region list rather than the head
Recursively forward-combine adjacent free regions
Add support for forward-combining free regions
[ci skip] Add AppVeyor badge to README
Bump version to v0.1.0-beta.1
[ci skip] Add license and description to Cargo.toml