updated maven and adapted aether, also had to exclude old version of asm causing headaches
changed package for aether classes to org.eclipse and fixed where changed, current it compiles but tests fail NoClassDefFound org/sonatype/aether/RepositorySystemSession, not sure where that comes from
javadoc update removing sonatype aether reference
using new snapshot of plugin harness that should fix the problem once released
o use maven 3.1.0
o force the use of sisu's ASM (to avoid a conflict in testing)
o use new plugin testing tools which have been updated for maven 3.1.0 (to avoid aether conflicts)
Merge pull request #222 from jvanzyl/maven31

o use maven 3.1.0
updated to maven 3.1.1
prerequisite changed to maven 3.1.1
downgraded to pluging testing harness 2.1 since it works again with maven 3.1.1 in master
Support --incremental on dex
Merge branch 'master' into maven31

Conflicts:
	pom.xml
changed creation of repo session
updated plexus utils to get access to org/codehaus/plexus/util/xml/pull/EntityReplacementMap
still need 2.2-snapshot of plugin testing
fix for har file lookup specific to architecture
removed sisu plexus dependency hack
using enforcer plugin to ensure Maven >=3.1.1
[travis-ci] Download, install and use Maven 3.1.1

There is no reason for red build while waiting for Travis CI team to
make Maven 3.1.1 available out of the box.

Signed-off-by: Mykola Nikishov <mn@mn.com.ua>
Merge pull request #237 from manandbytes/travis-mvn311

[travis-ci] Download, install and use Maven 3.1.1
Use SdkConstants for classes.jar