Refactor Go implementation to use best practices

[epelc]

Refactor and clean up token generation for go to use the latest best practices(everything besides making this repo go gettable).

• Remove all panics and add proper error handling
• Add timeouts to http client and context for production usage
• Use stdlib builtins where appropriate(ie basic auth)
• Several performance improvements by not repeating work
• Update error to use go format of lower case error strings

Update README.md to match api

Update go readme to match api.

• Fix language reference "Go programming language" not "GO Lang"
• Remove unused queryParams option
• Update install/setup docs. This file does not require go install since it is using only the standard library. Also these docs were using incorrect syntax anyways.

[epelc]

This also has many naming convention fixes. You can find official recommendations here.