~str -> StrBuf
Merge pull request #129 from mvdnes/str_to_strbuf

~str -> StrBuf
temporarily switch to the official nightly.
language changes: StrBuf -> String.
language changes: {,Total}{Eq,Ord} -> {Partial,}{Eq,Ord}; rand -> std::rand.
language changes: suppressed some warnings.
Add Cargo.toml
Merge pull request #131 from AndreZSanchez/master

Add Cargo.toml