LANG-1016: NumberUtils#isParsable method(s). Thanks to Juan Pablo Santos Rodríguez.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/lang/trunk@1609273 13f79535-47bb-0310-9956-ffa450edef68
Tiddy up JavaDoc

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/lang/trunk@1609277 13f79535-47bb-0310-9956-ffa450edef68