BTreeMap extracted from std for the purpose of adding experimental methods without having to recompile all of rustc.
To enable compilation, did the following changes:
- Moved mod.rs to lib.rs
- Set the toolchain to nightly
- Added the list of unstable features to lib.rs
- Commented out all the rustc only attributes (rustc, stable, unstable, ...)
- Removed "may_dangle" where it was present and accordingly removed unsafe from drop