updated and improved search api

[007vedant]

Endpoint => /api/users/search

Updates => expects params along with endpoint unlike previously when inURL args were required.

params -> hid & name
both the parameters are optional
suppling both the params simulataneously results in bad request(obviously)

Usage =>

1. /api/users/search
   hitting the url without any params returns response with details of all the healthOfficials in the database.

2. /api/users/search?hid=
   hitting the url with hid returns response with details of the healthOfficial queried against it.

3. /api/users/search?name=
   hitting the url with name returns response with details of all healthOfficials with similar names. (uses regex for string matching)

4. /api/users/search?hid=&name=
   bad request 400