Remove generation of docs (grpc-ecosystem#183)

Docs will now be only in code / in godoc.org.

We should remove the auto generation of docs from this repo, as much as it was nice to have them alongside the code in github it is normal go practice to look for most documentation via godoc.org.

The libraries that we have been using to generate the github markdown are no longer maintained and updated in the godoc codebase itself have meant that we would also have to update these dependant libraries ... which I do not think we should take.

Author: domgreen

.travis.yml

@@ -15,7 +15,6 @@ install:
   - dep ensure
 
 script:
- - make checkdocs
  - make test
 
 after_success:

DOC.md

@@ -11,8 +11,6 @@
 
 [gRPC Go](https://github.com/grpc/grpc-go) Middleware: interceptors, helpers, utilities.
 
-**Important** The repo recently moved to `github.com/grpc-ecosystem/go-grpc-middleware`, please update your import paths.
-
 ## Middleware
 
 [gRPC Go](https://github.com/grpc/grpc-go) recently acquired support for
@@ -24,7 +22,7 @@ These are generic building blocks that make it easy to build multiple microservi
 The purpose of this repository is to act as a go-to point for such reusable functionality. It contains
 some of them itself, but also will link to useful external repos.
 
-`grpc_middleware` itself provides support for chaining interceptors. See [Documentation](DOC.md), but here's an example:
+`grpc_middleware` itself provides support for chaining interceptors, here's an example:
 
 ```go
 import "github.com/grpc-ecosystem/go-grpc-middleware"