Added login and create login functions

[RamiDari15]

In this Pull Request i have changed the sever.js file adding two new methods inside. I created two post methods. The first post method is creating login information which ensures that the email and password field is filled in, they are valid emails that end with @emich, and they are emails never used before with our application. The second post method validates the login email and password with the firestore database.

[abhagat8]

Hi Rami, thank you for adding the post method to your code. I think your code is very good and having validation and authorization in place will be huge for the app. With that and the way I have the database setup right now, we can finally run some test to make sure the authorization is working correctly and have our login system set.

[RamiDari15]

@abhagat8 I seen the database and agree that we do enough to merge both this weekend to test if the database and code connects

[mdlaroy]

Rami, awesome work on creating this so far. It was smart to check to make sure the emails haven't already been used! Maybe we could include more verbose error messaging so the user can be pointed in a more clear direction if they have an issue that isn't so obvious :) Thank you for taking the time to work on this!

[RamiDari15]

@mdlaroy thank you for your feedback I will work on adding the more clear instruction on what to do when a user needs the correct input

[RamiDari15]

@linchristina03 thank you for your input i'll work on adding those field into the backend check