fix(User-Menu): Change links, styling and functionality #OZF-650
fix(METRICS_URL): Missing semicolon
fix(Sass Variables): Replaced inline colors

Replaced hard coded colors with sass variables
fix(list-unstyled): Swapped for bootstrap list-unstyled
fix(User-Menu.js): OZF-650 Fixed indentation
fix(User-Menu Test): OZF-650 Updated unit test

Updated unit test to mock <Link/>
fix(User-Menu.js): OZF-650 Fixed indentation
fix(User-Menu.js): OZF-650 Fixed indentation
fix(User-Menu.js): OZF-650 Fixed indentation
fix(Header Styles): OZF-650 Fixed indentation
update(Webpack Config): Added HUD_URL variable
update(User Menu): Added HUD_URL links
fix(User Menu): Added HUD_URL DefinePlugin
Merge pull request #28 from ozone-development/user-menu

feat(User-Menu): OZF-650 Update User Menu design