admin feature added

[Subham142]

1) admin can fetch all the users 2)admin can fetch a particular user by its Id

Closes: #204

Type of change

What sort of change have you made:

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [x] Enhancement in the existing features
• [ ] Other

Mention any unusual behaviour of your code (Write NA if not)

Any unusual behaviour of your code

Checklist:

• [x] My code follows the guidelines of this project.
• [x] I have performed a self-review of my own code.
• [x] I have commented my code, particularly whereever it was hard to understand.
• [x] My changes generate no new warnings.
• [x] I have verified/tested my code by running it locally.

[Subham142]

@Namanl2001 please review it

[Subham142]

@Namanl2001 please approve this so i can work on different admin features

[Subham142]

Will you merge this ..or should I continue here?

It will better if raise issue for other features..will help me with the point.

[Subham142]

@Namanl2001 really sorry for poking again...I thought the updating backend ( adding routes and controllers) were a level 3...after this..merge I won't be needing to add extra routes or controllers..