Use maps with replace to escape characters

See benchmarks:

* http://jsperf.com/multiple-replacements
* http://jsperf.com/multiple-replacements-ii
Merge pull request #71 from fork-n-roll/feature/escaping-that-works-II

Escaping that works II.™
Fix undefined ENTITIES_MAP in $.render()
Merge pull request #77 from gardentechno/master

Fix undefined ENTITIES_MAP in $.render()
Add support for nested object

See #81
Merge pull request #82 from fork-n-roll/feature/nested-objects

Add support for nested objects