Improve compatibility with older version of lxml
Improve compatibility with Python 2.6

This fixes "AttributeError: ZipExtFile instance has no attribute 'seekable'"
[osgi.req] Fix AttributeError
[osgi.req] Proper way of getting version
[maven_depmap] Try to inject pom.properties only to ZIP files

See rhbz#1139180
[test] Fix maven_depmap tests
[test] Always generate nosetests.xml
[test] Temporarily disable maven.req tests

Some of the tests there need latest XMvn and I don't have it on my F20
machine.
Prep for 4.2.0 release
Bump version to 4.3.0-SNAPSHOT