Update docs to indicate need for tests requiring generator support (io.js / Node 4.x)

Author: techniq

CONTRIBUTING.md

@@ -18,6 +18,7 @@ When submitting issues on GitHub, please include as much detail as possible to m
 1. `cd js-data-sql; npm install; bower install;`
 1. Write your code, including relevant documentation and tests
 1. Run `grunt test` (build and test)
+  - You need io.js or Node 4.x that includes generator support without a flag
 1. Your code will be linted and checked for formatting, the tests will be run
 1. The `dist/` folder & files will be generated, do NOT commit `dist/*`! They will be committed when a release is cut.
 1. Submit your PR and we'll review!

README.md

@@ -76,6 +76,7 @@ When submitting issues on GitHub, please include as much detail as possible to m
 1. `cd js-data-sql; npm install; bower install;`
 1. Write your code, including relevant documentation and tests
 1. Run `grunt test` (build and test)
+  - You need io.js or Node 4.x that includes generator support without a flag
 1. Your code will be linted and checked for formatting, the tests will be run
 1. The `dist/` folder & files will be generated, do NOT commit `dist/*`! They will be committed when a release is cut.
 1. Submit your PR and we'll review!