This should prepare test resources for all subprojects. A WALA
developer should run this once before running any tests inside
Eclipse. Initially I'd hoped to make this more narrowly focused, but
Eclipse just doesn't have the infrastructure to deal with fine-grained
dependencies. On the other hand, running "./gradlew
eclipsePrepareTestResources" automatically for each build seems like
overkill, and could end up being rather slow. So for now we require
that the developer run this once, by hand.
Ben Liblit