v0.13.0

Adds support for order predicate (/parent/offspring[1])

Tag value selector support and dependency updates

Now supports queries based on tag values (ie, //parent[offspring='value']).

Upgraded dependencies.

Merge pull request #14 from dsummersl/prerelease

Patch level updates and document updates.

Hyphen support.

This version supports hyphens in a XML tag name.
Also updates dependencies.