Removes a range of characters from the content.

Parameters:

start The starting index in the range, inclusive. This must be >= 0 and < the end.

end The ending index in the range, exclusive. This is one-past the last character to delete (consistent with the String manipulation methods). This must be > the start, and <= the length of the text.

`start`		The starting index in the range, inclusive. This must be >= 0 and < the end.
`end`		The ending index in the range, exclusive. This is one-past the last character to delete (consistent with the String manipulation methods). This must be > the start, and <= the length of the text.