simplified the maven-plugin-plugin configuration

Useless tricks are no more, as well as the useless so-called help mojo.
It seems rather useless since the help:describe goal does a pretty good
job with that.
the working directory is now configurable

It's the project's base directory by default for both the ant task and
the maven plugin. Test cases file names are relativized when they belong
to the working directory tree.
added a .gitignore file

Because having a local .gitignore is not an excuse for not having
project-level one.
added a license file
added a true minimal-configuration maven test

The previous minimal-configuration test is renamed to run-war, because
well, it runs a war project in a servlet container for the varnish
tests.
added a failing maven test

Just to make sure the plugin actually fails when a test case fails...
added a reports-directory maven test

The test simply configures a different directory for the reports and
makes sure the report is written there and not in the default location.

It uses the maven-verifier-plugin to check the files on disk, as do the
other tests from now on.
better handling of ant tests

It now works in a similar fashion than the maven-invoker-plugin. There
is now one buildfile called by the maven-antrun-plugin, and actual test
cases can be dropped in sub-directories. AntUnit's report appears in the
console instead of varnishtest logs.
added a bunch of antunit tests for failures
varnishtest-exec learned new reserved macros

Instead of letting varnishtest fail, varnishtest-exec does it faster.
added API checks with the clirr-maven-plugin

Sounds like a must-have when building a library, better now than never.
added the building blocks for the documentation

It's a bit twisted but at least, it is possible to generate a proper
maven site. Manual documentation still needs to be written.
added a REAME file
added dependency convergence report
added documentation in the Maven site

Generating the documentation was tedious, writing the bits that can't be
generated was just boring. Good thing it's finally done.
added a changelog in the documentation
[maven-release-plugin] prepare release varnishtest-exec-0.2
[maven-release-plugin] prepare for next development iteration