Create subpackage httphandlers, refactor getRootURL

[fawick]

To start factoring out the HTTP handlers I suggest a new package httphandlers. I decided to not name it http to distinguish it from net/http.

For the initial commit of this package I decided to move the functionality in func getRootURL out and remove the dependency on labstack/echo. The old function that uses echo is kept as a convenience function in main.go.

Update #40.

[brendan-ward]

@fawick this looks great. Only comment is on package name. What about simply handlers, in the spirit of gorilla/handlers.

[fawick]

Okay, renamed to handlers.