Mention which style guide takes precedence and import practices

Closes #1223

Author: brettcannon

CODING_STANDARDS.md

@@ -1,5 +1,5 @@
 ## Coding guidelines for TypeScript
-* The following standards are inspired from [Coding guidelines for TypeScript](https://github.com/Microsoft/TypeScript/wiki/Coding-guidelines).
+* The following standards are inspired from [Coding guidelines for TypeScript](https://github.com/Microsoft/TypeScript/wiki/Coding-guidelines) (which you should follow when something is not specified in this document, although any pre-existing practices in a file being edited trump either style guide).
 
 ### Names
 
@@ -31,6 +31,11 @@ Use undefined. Do not use null.
 
 Use single quotes for strings.
 
+### Imports
+
+* Use ES6 module imports.
+* Do not use bare `import *`; all imports should either explicitly pull in an object or import an entire module, otherwise you're implicitly polluting the global namespace and making it difficult to figure out from code examination where a name originates from.
+
 ### Style
 
 * Use arrow functions over anonymous function expressions.