Throw error on invalid extraProperties

See issue #10
Quote fix
Merge branch 'master' into extraProperties
add test
remove erroneous file
some example dataTypes documentation
Merge branch 'master' into dataTypes-documentation
added get and default documentation
some more rendering cleanup
Merge pull request #46 from AmpersandJS/extraProperties

Throw error on invalid extraProperties
Updates based on feedback from pull request
space things out a bit more, still getting used to markdown. :)
Add travis.yml
Merge pull request #107 from AmpersandJS/add-travis

Add travis.yml
forgot to remove some previous docs
fix for PR suggestions, also changed 'AmpersandView' to 'AmpsersandState'
Merge pull request #103 from mmacaula/dataTypes-documentation

Data types documentation
Don’t delete properties from mixin objects passed to .extend

Fixes: #68, #110
Merge pull request #111 from AmpersandJS/fix-110

Don’t delete properties from mixin objects passed to .extend
4.4.1