Now ksoap2 has a possibility to skip properties with null values from the soap request.
Now if our custom class (which implements KvmSerializable) inherits from AttributeContainer then we also serialize the attributes to soap request
Improvement for extends SoapSerializationEnvelope class
Merge pull request #44 from robocik/branch5

Improvement for extends SoapSerializationEnvelope class
Merge pull request #42 from robocik/branch1

Skip null properties
Merge pull request #43 from robocik/branch3

Serialize attributes from any class inherits from AttributeContainer