Seperating doctor registration and patient registration
functionality for captcha to work
-added captcha logic for doctor registration as well in DoctorController.java
-removed unwanted else statement from PatientController.java
-seperated out the registration mapping in LoginController.java
-two seperate buttons for register in signin.jsp
-seperated registration.jsp into doctorregistration.jsp and patietregstration.jsp
-removed DocSignUpBtn.jpg to make doc/patient button uniform
-removed Register.jpg and added RegisterDoc.jpg and RegisterPatient.jpg