Improve InjectMojo annotation processing

[elmuerte]

This pull request addresses issue #244

The JUnit MojoExtension is now compatible with other parameter resolvers.

The various annotations can now also be used on class or even parameter levels.

@InjectMojo can be used on methods and individual parameters.

@Basedir can also be used on the test class. Which can then be overridden on a test method.

@MojoParameter can be defined on test class, test method, or individual parameters. They are processed in that order, giving the values defined on the parameter the highest priority.

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