Docs: note fix for class loader cache
Build cleanup, publish launcher normally, pull it normally in scripted plugin

Still want to deploy the launcher to the previous path for compatibility with
existing scripts so that the transition to 0.13 is not impeded.
Update instructions for building from source
update to Scala 2.10.2 final
source compatibility of ClasspathUtilities.isArchive for sbt-assembly

default parameters and eta-expansion don't interact well
build with 0.12.4-RC3
JLine 2.0 loads the -Djline.terminal=<class> option from the context loader, so set that in the launcher