Update watch.js

This fixes remy/nodemon#399, fixes remy/nodemon#392, fixes remy/nodemon#376 by make the drive letter upper-case.

This is caused by `path.join`, the returned path has a lower-cased drive letter:
```text
> path.join('C:\\', 'Test')
'c:\\Test'
```

Later check path against rules using minimatch, it failed as `options.nocase` is `false` by default.
Merge branch 'master' of github.com:JixunMoe/nodemon into JixunMoe-master
Tidy code to match coding style
Merge branch 'JixunMoe-master'