* deprecate `0c`, `0C` prefix for octal literals
Deprecates the previously allowed syntax of `0c` and `0C` as a prefix for
octal literals to bring the literals in line with the behavior of
`parseOct` from parseutils.
* add `msgKind` arg to `lexMessageLitNum` for deprecation messages
* change literal tests to check all valid integer literals
Also adds the `tinvaligintegerlit3` test to test for the (still)
invalid `0O` prefix.
