Increase FullSystemITest membership timeout

This has failed a couple of times, and we have a little evidence that
it's just barely missing. I don't like to just increase timeouts when we
see failures, but I'm not finding a better way to do it right now. Let's
increase the timeout for now, and if we still see failures, maybe take
another approach.
Merge pull request #70 from mbyron01/master

Updated pom.xml to support Maven-Repo standards
fix typos
Merge pull request #71 from clinedome-work/bump-membership-timeout

Increase FullSystemITest membership timeout
Replica should ignore out-of-date DecisionHints

Defensively check for slotNum usefulness before applying the
DecisionHint. Otherwise, if we got an old duplicate or a mis-sent
DecisionHint it could do something nasty.
Merge pull request #58 from snatchev/fix-typos

fix typos
getRandomMember returns Try instead of Option

Try maps much more cleanly to what getRandomMember is hoping to do. This
setup models failure a little more gracefully, and will be useful in
rebuilding some of our catchup logic.
Merge pull request #73 from clinedome-work/ignore-old-decisionhints

Replica should ignore out-of-date DecisionHints
Merge pull request #74 from clinedome-work/getrandommember-to-try

getRandomMember returns Try instead of Option
Create CatchupActor, CatchupSupervisor

Reworking catchup process. Mutate window size based on historical
success/failures, similar to TCP slow-start / congestion-avoidance.
These actors provide the basis for this, and included here are the
config options we'll need. Nothing's hooked up.

Also included are the new messages it'll use.
Wire in new catch-up algorithm

Wire the new catchup actor and supervisor into place. Includes reworking
a *lot* of the way the PaxosStateBridge works, but hopefully putting it
in a much more understandable state than before. Also includes changing
SiriusPersistenceActor so that it uses the new LogSubrange methods.
Remove old catch-up remnants

Remove GapFetcher*, and the messages we used for sending around
subranges of logs. Don't need 'em anymore!
add contributors.md file
Merge pull request #76 from tbarker9comcast/create-contributing-page

add contributors.md file
Add MBean monitors for window, ssthresh

This stuff will be very helpful to have accessible through JMX. You
could conceivably detect network badness by a lower-than-normal
ssthresh, and it might be fun to graph window. Just suggestions, YMMV.
Simplify Catchup Request logic, more config

Eliminate CatchupActor in favor of ask(). In addition, make more of the
catchup params configurable, and add some explanatory documentation to
the CatchupSupervisor.
Merge pull request #75 from clinedome-work/rework-catchup-algorithm

Rework catchup algorithm
Make akka max-frame-size configurable

Also, make it actually do something. We currently specify it in a
non-functioning way for the version of akka we're using. Apparently the
key for that piece of configuration changed with the versions.

128K is the default for Akka, which is how it's been de facto configured
since the last release. Changing the default to 1024K, which is a little
more real-world useful for applications using Sirius, particularly WRT
catchup messages.

Also, make send/receive buffers scale with max-message-size.
Merge pull request #72 from clinedome-work/akka-max-frame-size

Make akka max-frame-size configurable