Removed the need for the shell script to set the plugin version

Now the tests will automatically use the current version of the plugin
Merge branch 'remove-shell-script' of https://github.com/cdow/xsbt-web-plugin into cdow-remove-shell-script

Conflicts:
	src/sbt-test/web/jetty-dep-conf/project/plugins.sbt
	src/sbt-test/web/jetty-env/project/plugins.sbt
	src/sbt-test/web/jsp/project/plugins.sbt
	src/sbt-test/web/multi-jetty/project/plugins.sbt
	src/sbt-test/web/sbt-provided/project/plugins.sbt
	src/sbt-test/web/servlet-direct/project/plugins.sbt
	src/sbt-test/web/servlet-nodup/project/plugins.sbt
	src/sbt-test/web/servlet/project/plugins.sbt
	src/sbt-test/web/tomcat/project/plugins.sbt
	src/sbt-test/web/war-classpath/project/plugins.sbt
	src/sbt-test/web/war-contents/project/plugins.sbt