Add api_routing

```
$ vim config/routes.rb
```
Refactoring users_controller

```
$ vim app/controllers/v1/users_controller.rb
```
Generate entries_controller

```
$ railg g controller v1/entries
$ vim app/controllers/v1/entries_controller.rb
```
Generate lates_controller

```
$ rails g controller lates_controller
$ vim app/controllers/v1/lates_controller.rb
```
Merge branch 'master' into api_innparusu
Add lectures_controller
Add sign_in

```
$ vim app/controllers/v1/users_controller.rb
$ vim config/routes.rb
```
Merge branch 'master' into api_innparusu
Fix REST

```
$ vim app/controllers/v1/lates_controller.rb
$ vim app/controllers/v1/lectures_controller.rb
$ vim config/routes.rb
```
Merge branch 'master' into api_innparusu