ARQGRA-290: AttributeIsPresent condition fixed

* It now counts with empty attributes' values and claims those empty
 attributes as they are not present

* tests for this added
ARQGRA-290: tests extended
updated 'toString()' method of Element* conditions to contain negation
ARQGRA-288: removed need for Drone factory wrappers - replaced with Ehnancer
ARQGRA-286: support for PhantomJS debugging + big refactoring
ARQGRA-289: ignore tests failing on JavaScript interface invocations
ARQ-1351: fixed Drone integration with augmentation
deleted overriding graphene configuration in ftest
ARQGRA-289: workaround for Google Chrome freeze during JS execution