Implement SetStrict with tests
[FEAT] Implement map data structure
added union, intersection, difference, toArray, fromArray, and copy methods to set.  changed set init to use Object.create(null)
add Trie constructor and basic functions
add initial tests for trie
add stringsFromPrefix function to Trie
add test coverage for stringsFromPrefix on Trie
remove console.log statements from Trie implementation
Merge pull request #12 from nickb1080/set-strict

Implement SetStrict with tests
Merge pull request #14 from nickb1080/map

[FEAT] Implement map data structure
Merge pull request #15 from peterkhayes/master

JSON.stringify for set keys.  New set methods added.
update readme with information about use of Trie
Merge pull request #16 from jrhdoty/master

Adds Trie data structure
[DOC] Update docs to reflect many changes and pull requests