Add leading comment. This will be appended to the list of leadingComments.
Note: # will be prepended automatically if line is not empty and does not have # at the start.
The last new line character will be removed if present. Others will be replaced with whitespaces.
Add leading comment. This will be appended to the list of leadingComments. Note: # will be prepended automatically if line is not empty and does not have # at the start. The last new line character will be removed if present. Others will be replaced with whitespaces.