New constructor and possible to add hints after creation
Merge pull request #100 from pruivo/t_locality_hints

New constructor and possibility to add hints after creation

As requested by Fabio (from Algorithmica):

"Maybe you can provide 2 new constructors: 
1) without arguments (in this case I need an extra method to add the key/value pairs),
2) with argument String[]"

It looks like JRuby does not like LocalityHints(String... hints)