add: :new: methods to validate properties (maybe solved #4 ?)
add: :new: methods to validate properties (maybe solved #4 ?)

- ensurePropertyExists
- ensureMethodExists
- ensurePropertyHasSetter
- ensurePropertyHasGetter
- getPropertySetter
- getPropertyGetter

Change default implementation of __get and __set methods, using those
methods

Signed-off-by: Nelson Martell <1c7378940213ad41faa69fa57748d6af8c629a73@yahoo.es>

nelson6e65/php_nml,nelson6e65/php_nml