Don't store TrafficInjections in a separate datastructure!

Was a bad idea to begin with: screwed up MCS's, and made it hard to pretty
print events.

Now store the dp_event in the json trace
Make TrafficInjections display nicer
Don't require topology param
Add option to display TrafficInjections for old traces
Remove cruft from pretty_print
Add tool for removing need for TrafficInjection backwards compatibility
typo in mkdir_p
Add a forker class: spawn children and return results via XML-RPC
Return violations via forker rather than exit code
Merge client's runtime stats
Remove extraneous print
Move runtime stats class to bottom of file
STS socket s/b non-blocking
Merge branch 'master' of github.com:ucb-sts/sts into scalability