Reload config on update - Updated

[mumblepins]

Watches for changes to config.json and reloads config. Updated version of #357. Addresses some of the notes on that pull request, cherry picked on to current code base, and improved some refresh handling.

What kind of change does this PR introduce? (check at least one)

• [ ] Bugfix
• [X] Feature
• [ ] Code style update
• [ ] Refactor
• [ ] Build-related changes
• [ ] Other, please describe:

The PR fulfills these requirements:

• [X] All tests are passing?
• [X] New/updated tests are included?
• [X] If any static assets have been updated, has ui/bindata.go been regenerated?
• [X] Are there doc blocks for functions that I updated/created?

If adding a new feature, the PR's description includes:

• [ ] A convincing reason for adding this feature (to avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it)

Other information: