breaking: remove .get{Scope name}Api() methods

BREAKING CHANGE: `.get{Scope name}Api()` methods have been removed.

Before you could do this

```js
const reposApi = github.getReposApi()
```

Which is the same as doing

```js
const reposApi = github.repos
```

So we removed it :)

lib/index.js

@@ -231,11 +231,6 @@ var Client = module.exports = function (config) {
 
           if (!self[section]) {
             self[section] = {}
-                        // add a utility function 'getFooApi()', which returns the
-                        // section to which functions are attached.
-            self[toCamelCase('get-' + section + '-api')] = function () {
-              return self[section]
-            }
           }
 
           self[section][funcName] = function (msg, callback) {