Address documentation issues from PE-D

[Andrew22Teoh]

• Closes [PE-D][Tester B] Command parameter constraints not clear in UG #226 by including a short writeup in the add command feature description with a hyperlink to the contact field requirements
• Closes [PE-D][Tester C] Valid input for email field is inconsistent between User Guide and App. #227 by correcting User Guide to match error message and regex
• Closes [PE-D][Tester A] Incorrect Date Format Example in User Guide for Add Command #232 by fixing the typo about date
• Closes [PE-D][Tester D] Inconsistent Date Format Handling in UG #235 by fixing the typo about date
• Closes [PE-D][Tester A] Address Field Not Displayed in UI for Added or Edited Persons #234 and closes [PE-D][Tester A] Remark Command Does Not Display Remark in UI #238 by documenting in the UG that it's not supposed to
• Closes [PE-D][Tester D] Incomplete Name Capture for Indian Naming Convention ("a/p" Format) #229, closes [PE-D][Tester B] add command gives incorrect error message when using nonexistent parameter keywords  #236, and closes [PE-D][Tester C] User unable to add inputs with prefixes for other fields #237 by requesting that the user appends a special character to the front of the prefix.
• Closes [PE-D][Tester B] ec/ error message unclear #231 by recording it as a known issue in the UG

[codecov]

Codecov Report

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