MIS updates - Student registration template


**Functionalities implemented:**

**1) submit-button label toggles: 'Register' on create/register-form and 'Update' on edit-form**
 
   - File modified:
   
     1) templates/ndf/student_create_edit.html
     
**2) For few attributes of Student GSystemType - Validations implemented & New values added**
 
   - Name (first_name, middle_name & last_name) input fields accept only letters
   
   - Date (dob, 12_passing_year & registration_year) input fields made readonly; can be set only via date-widget
   
   - Files modified:
   
     1) ATs.csv file
   
        - editable column's value: Change to FALSE for following fields - dob, 12_passing_year & registration_year
     
        - validators column's value: Set as ["text", "^[a-zA-Z]+&"] for following fields - first_name, middle_name & last_name
        
        - complex_data_type column's value: New values added for degree_name field which are as follows - M.A., M.Sc. & M.S.W.
     
     2) templates/ndf/html_field_widget.html
     
        - readonly Attribute/property added: if editable is FALSE, set this attribute for respective input html element(s)
        
        - pattern Attribute/property added: if validators length is >1, then assign 1st index value of validators to this attribute for respective input html element(s)

**3) Disable GAPPs for time being from college groups: Task, Batch, Meeting**
 
   - Script modified to disable above given GAPPS from college groups
   
   - File modified:
   
     1) management/commands/mis_college_group.py