[WIP] Improve cross-browser support

Every browser outputs stack data differently. Aside from basic format
differences, IE, Chrome, Firefox, and Safari each output different
column values for the same exception.
  - IE uses the column at the start of the statement that caused the
	exception.
  - Chrome uses the column at the start of the term (e.g., variable
	name) that caused the exception.
  - Safari uses the column just after the term that caused the
	exception.
  - Firefox doesn't output column numbers, only line numbers.