SliceUnit implementation and serialization tests.
Serialization/Deserialization test for Specification.
Rename test-helpers bundle to mqnaas-test-helpers.
New bundle with general test helpers.
Move ReflectionUtils to new bundle.
Merge pull request #64 from adrian-rosello/feature/slice-unit-def

Feature/slice unit def



Pull request defines a slice unit. It's only based on a type and name. For example: A VLAN slice unit will be defined as a SliceUnit with DISCRETE type and VLAN name.

Include tests for serialization/deserialization of the Specification and SliceUnit classes.

Fixes CON-54