First cut at implementing hierarchical assertion support (issue #2).
Improved reliability of chosing super assertion class. Removed commented code. Added command-line option support.
Added support for public fields into the hierarchical generator (issue #15).
Updated documentation in the AssertionGenerator interface.
code cleaning and refactoring
Merge remote-tracking branch 'kriegfrj/hierarchical-issue-2'

Conflicts:
	src/main/java/org/assertj/assertions/generator/BaseAssertionGenerator.java
	src/main/java/org/assertj/assertions/generator/Template.java
	src/main/java/org/assertj/assertions/generator/description/converter/ClassToClassDescriptionConverter.java
	src/test/java/org/assertj/assertions/generator/description/converter/ClassToClassDescriptionConverterTest.java
Fix NPE when generating assertion for an interface with hierarchical
strategy as interfaces have no superclass.
Fix generated assertions with hierarchical
strategy for nested classes.
Fix real number assertion generation when using hierarchical strategy.
Generated assertions classes should not be final to be used in soft
assertions that require proxying them.
Add script to build both assertion generator and maven plugin