Improvements to Compensation Calculator

• Rename "Benchmark" to "NYC Compensation" to clarify where the benchmark applies / comes from. Or NYC Benchmark? Since comp in NYC > this number?
• Add brackets to summation term on https://about.gitlab.com/handbook/people-operations/global-compensation-framework/#compensation-calculator
• Make sure the calculator adds all inputs and outputs to the url so people can paste a link. Example URL: https://about.gitlab.com/jobs/developer?city=austin&country=us&experience=1.0&level=intermediate&currency=USD&low=53101&high=79651
• Change experience ranges to more granular:
  • little 0.8-0.9
  • below average 0.9 - 1.0
  • above average 1.0 - 1.1
  • a lot 1.1-1.2

Other improvements that are related:

• #975 (closed)
• #976 (closed)