Fix NPE in version macro if no qualifier is present.

Includes unit test.
Use bnd.jar instead of bndlib.jar as bnd.jar contains the embedded repo.
[bnd-maven-plugin] Use testsrc/testbin instead of src.test/bin.test
Fix typo in defaults.bnd
Check bnd project version and maven version match. Fixes #378.

They should match literally, except that the Maven -SNAPSHOT suffix is
mapped to the Bnd .SNAPSHOT qualifier.
Unit tests included.
Run the bnd testing framework as part of the integration-test phase

Fixes #377
Unit tests for the BndTestRunner Mojo
Change the package type from 'bundle' to 'bnd'.

The 'bundle' package type is already used by the maven-bundle-plugin, so
to avoid any confusion I'm changing the package type to 'bnd'. Still to
do is look at how to use this plugin with a plain 'jar' package type.
Update README.md
Update README.md