Fixed forwarding from spring boot -> vuejs.

[dogeared]

Forwarding from spring boot -> vuejs is currently busted.

Right now, it's handled inside the BackendController which is problematic because (a) it's a RestController and (b) it's only handling /api/** paths since it has a RequestMapping at the top of the class.

This PR introduces a Controller called VueForwardController whose only job is to properly handle the forwarding to the view app in case a user puts a full URL directly in the browser.

[ubaldop]

I think this PR might be very helpful. As a side consideration I am wondering if the regex here could be too much restrictive (e.g. it seems not forwarding routes with more than one token, such as /hello/world/yada/yada). What about to have a route more restrictive like the following?

@RequestMapping({"/{path:[^\\.]*}", "/**/{path:^(?!index\\.html|api|actuator).*}/{path:[^\\.]*}"})

[jonashackt]

@isneezy also fixed the problem with #92, but that might be more comprehensive. So I went with his solution and will close your PR in favour of #92. Thanks anyway and I hope you test your scenario also with the new version 😃