Fix typo in serialization method name.
Add Pregelsphere
Executor services use daemon threads which prevents lingering threads at job end.
Make 'closed' status in hash join atomic to prevent multiple concurrent closing.
Added missing googleapi
Fix concurrent memory release in HashJoin cancel case.
Minor formattings.
Add "stratosphere-yarn" sub-project

based on https://github.com/hortonworks/simple-yarn-app

Build debian package only with special profile for that (to speed up the build)
Build uber-jar of stratosphere (for super-handy yarn deployment)

Old commit messages (from rebase:)

advanced configuration file handling (maven and jar magic)
Command line arguments for client (not yet done)

Change JobManager startup to allow external control
Use environment variables to pass variables to ApplicationMaster
Use contstants for settings
Fix CLI options
minor refinemens (pact-hbase dependencies)

Yarn runs with HDFS
jar files and configs are now shared using hdfs
many many deployment bug fixes
uberjar is automatically uploaded to dopa server
generate debian package for dopa; new configuration parameter for yarn client to create default yaml
move yarn to separate profile to disable it individually

This is a combination of 5 commits:
extended submission client

minor yarn refinements

some minor fixes

moved print usage
Implement superstep abstraction on Nephele readers/writers.
Cleanup Nephele readers/writers.
Relieve 1. travis worker by deploying only one version to sonatype
Rename Pregelsphere to Spargel
Make all scala rich stubs have apply method instead of specific name

Before, MapStub required the user to specify a map() method, now they
specify an apply() method. This is more in line with how Function1[] and
so one works and also the same across all operators.
Add deferred updates to workset iterations (issue #21) and fix chaining of iteration state updates (issue #123)
Formatting and minor cleanups in iteration code.
remove discoveryManager
yarn now also starts the web interface
extended pact-client to nicely support remote execution.
unified 'run' and 'remote' in pact-client
Fix issue of selecting wrong class loader in combiners.
fix minor build issue: deploy uber-jar only if yarn version is build