util-invariant should use logger under the hood

[chasefleming]

invariant from the util-invariant package was created before the logger package. It should be converted to use util-logger under the hood. In it's current state, it would replace the console.error and throw with util-logger.

Additional functionality that would be nice to add in this case are also:

• If syntax is the same, then default to util logger throwing an error
• Add another arg that if set lets you change the logger level (e.g. to warning). This would also stop the throwing of the error.