Fixes for WinBUGS sampling

 * Remove 'deviance' from results
 * Add note on invoking R on Linux to make R2WinBUGS work
Validation testing infrastructure

Verify sampling with JAGS, OpenBUGS, WinBUGS against the known
baseline (Java-generated code run in JAGS).
Add rank probabilities for some examples

Could not generate for the welton-*.gemtc examples due to bug in
gemtc 0.1-2.
Command used to generate summaries
Fix another bug with two-treatment networks (issue #629)
Integration test: generate rank probability verification samples

Using the 0.2 code for the welton-*.gemtc examples because 0.1-2
does not handle them correctly (all other statistics have been
checked against 0.1-2 prior to this).