update rust-crypto
Update Travis to use official Rust support
Update for rust master
Merge pull request #390 from ebfe/fix-build-master

Fix build with rust master
Merge pull request #391 from Arcterus/travis-official

Update Travis to use official Rust support
Update for latest Rust
Remove all warnings (at least on Linux)
Update for rust RFC 52 changes
Merge pull request #392 from Arcterus/fix-build

Update for latest Rust and remove warnings
Merge pull request #393 from ebfe/rfc-52

Update for rust RFC 52 changes