master is broken with Go 1.7.4

[ghost]

Issue Description

Pulling master with go get -u github.com/labstack/echo brings up multiple errors due to features not available on Go 1.7.4 being used.

Checklist

• Dependencies installed
• No typos
• Searched existing issues and docs

Expected behaviour

Echo to build without failure

Actual behaviour

../go/src/github.com/labstack/echo/bind.go:47: ute.Field undefined (type *json.UnmarshalTypeError has no field or method Field)
../go/src/github.com/labstack/echo/echo.go:448: undefined: url.PathUnescape
../go/src/github.com/labstack/echo/echo.go:684: e.TLSServer.Close undefined (type *http.Server has no field or method Close)
../go/src/github.com/labstack/echo/echo.go:687: e.Server.Close undefined (type *http.Server has no field or method Close)
../go/src/github.com/labstack/echo/echo.go:693: e.TLSServer.Shutdown undefined (type *http.Server has no field or method Shutdown)
../go/src/github.com/labstack/echo/echo.go:696: e.Server.Shutdown undefined (type *http.Server has no field or method Shutdown)

Steps to reproduce

1. Install go-1.7 from Debian Stretch repos
2. Pull with: go get -u github.com/labstack/echo

Working code to debug

nil.

Version/commit

master (commit d36ff72)

[ferhatelmas]

@mission712 #1100 try vendoring.

[vishr]

@mission712 We officially don't support go 1.7 & 1.8 https://github.com/labstack/echo/blob/master/.travis.yml#L2

[ghost]

@vishr https://echo.labstack.com/guide/installation claims otherwise, though. Consider updating the page.
EDIT: Check out labstack/echox#70