build: updating ant build to generate api docs with apigen
more generic ignore rules for lib/data/conf directory
api docs: adding ESys package docblock annotation wherever missing
ESys_ValidatorRule: moved validator rule classes to their own file to improve PSR-0 autoload support
ESys_ValidatorRule_NotEmpty: new validator for enforcing non-empty values. (fails on empty string, whitespace strings, and null)
updating changelog for release
Merge branch 'release/1.2.9' into develop