Check whether a list of properties exists within a given object

Status: **Opened for visibility**

Decided to go with a single string argument for supplied properties, delimited by a period, vs. each property supplied as a separate argument, as discussed with @donnielrt.
 
Reviewers: @donnielrt 
  
## Changes
- Added checkProperties.js file to src/utils/ 
- Added $.checkProperties() function
- Added checkPropertiesTests.js test file to tests/unit/utils/
- Added tests for negative and positive conditions
  
## How to test-drive this PR
- Run `grunt test` in the terminal
TESTS! Woo!