[lang] StringUtils.ordinalIndexOf() and INDEX_NOT_FOUND

[Gary Gregory]

Hello All,

I've added StringUtils.ordinalIndexOf() and introduced a new constant
StringUtils.INDEX_NOT_FOUND = -1. Currently, only ordinalIndexOf uses this
constant. 

I would like to get a fell if folks think that replacing (where
appropriate), the -1 magic number usage in StringUtils with this constant is
a good idea or refactoring gone wild.

Thanks,
Gary