Merge pull request #19 from btbonval/master

Support built-in Math functions for #3
Added better math parsing logic
cleanup after better math parsing
Slightly modified math eval code so that Math functions can be called in-place (eg. 'abs(totalPopulation)')
Merge branch 'master' of https://github.com/WasabiFan/3D-US-Data-Map
Simple fix to make equations whitespace-independent
Moved deg/rad ratios to Global.js file
Added error handling and reporting so that incorrect formulas in the mathBox don't crash the app
Merge branch 'master' of https://github.com/WasabiFan/3D-US-Data-Map
Dynamically find and handle raw dataset property names.