Fix #297: Add flag to hack away lingering calls to Predef.classOf

This fixes a bug which would have been introduced with the next
revision. The commit merely exists for spearation of concerns.
Configure sbt to pull scalalib depencencies for cross compile
Generalize scalaVersion in partest suite
Add 2.11.0-M8 to partested versions
Add 2.10.3 and 2.11.0-M8 to travis build
Merge pull request #300 from gzm0/full-cross-compile

Full cross compile support for build-scripts and partest
Emit call graph information in .sjsinfo, for upcoming dce.

No dce is actually performed yet. This commit only emits the
necessary information.
Perform reachability analysis for dce.

The dce itself is still not actually done. The
preoptimizeJS task performs reachability analysis, from
which dce will be able to work to produce the optimized
output.