Case insensitive command word

[dlimyy]

Steps to reproduce

addclient n/John p/91234567

Expected Output

New client added: John; Phone: 91234567

Actual Output

I think it would be good if you could make the command keyword not case sensitive to allow user more flexibility in typing the command. Alternatively, if the command word has to be in this format, you could look to include an exception message such as Did you mean addClient instead