* fix singleton() so it actually works * insert file format version in written files * add getSetValues() method for listing the valid values for a set value
* fix singleton() so it actually works
* insert file format version in written files
* add getSetValues() method for listing the valid values for a set value


marcosptf/pear-core,marcosptf/pear-core,marcosptf/pear-core,marcosptf/pear-core,marcosptf/pear-core,marcosptf/pear-core