Deal with named parameters under same level (shared) and raise
proper `SharedKeyError` exception.
This is a non-backward compatible change aims to solve result
mapping issues and tree lookup.
Now README covers this under *Caveats* section and offers an
alternative organization of the paths used on the tree.
To avoid potential issues when using `master` instead of a locked
release, bump the version.
Extract Radix Tree implementation from `Beryl` project into an
standalone library to facilitate usage by other developers.
- Move `Tree`, `Node` and `Result` into `Radix` namespace
- Clenaup standalone README and describe usage
