This change is originally from pull request #682.

For a reason similar to ded37a2b,
better to run with non empty context path.

This helps us catch a typical error of not using ${rootURL} or
getContextPath() where needed.

[JENKINS-15156] Missing call to onCreatedFromScratch caused failures in MatrixProjectTest (when run from Surefire at least).

d62e95a9.

b5ed3199 already caught linkage errors but then unconditionally returned false from Util.isSymlink, which is wrong;
we want to fall back to the generic File.canonicalPath comparisons in this case.

Add run display name as an environment variable when RunParameter is used as a parameter.

Url with contextPath for non-standalone installs.

Conflicts:
	core/src/test/java/hudson/UtilTest.java

There are several incompatibilities in XStream 1.4 that resulted in our
changing the core, but according to the text search on all the public
plugins, none of these changes affect the 600+ plugins we have today.

However, it is still possible that there are some parts of XStream 1.3
that plugins depend on but the core doesn't depend on --- we won't be
able to tell those problems at this point.

target run's display name.

The environment variable will be named <PARAM_NAME>_NAME and will
contain the display name of the target build.

Not sure what has happened --- perhaps some of the markers were off and
that confused the update script?

Will need to watch out for the next RC run.

Add/update Chinese (traditional) translation.