Refactoring and Clean-up for Code Style and Fix Typo

### Refactoring & Clean-up for Code Style
* Rearranged the routes into its own modules & refactored those files to fit the Felix's code convention.
* Slight clean-up for all those source files directly lie under app directory. Most works are done by automatic format tools, so they won't lead troubles.
* None of the logic & functionalities were changed, except,
    * The `exports.begin` in `email-verification.js` now use absolute path for template file instead of relative one.
    
    See [this commit](https://github.com/Plypy/openmrs-contrib-id/commit/a3cf75baf9a8765e596242f51df8ada96151595d), and [this](https://github.com/Plypy/openmrs-contrib-id/commit/b3f3df321de94d5756de335a5cf3dd20d930ad02)

* It has been tested on my machine, everything seems to be fine.

### Typo Fix

See this [issue](https://issues.openmrs.org/browse/ID-19?jql=project%20%3D%20ID%20AND%20status%20%3D%20%22In%20Backlog%22%20ORDER%20BY%20priority%20DESC), and [this commit](https://github.com/Plypy/openmrs-contrib-id/commit/0e35b669fea3e5065407ab7de5b980fd7dde4423).