Cleaned up logging in slave, status update manager and executor driver.

Review: https://reviews.apache.org/r/10708

git-svn-id: https://svn.apache.org/repos/asf/incubator/mesos/trunk@1476338 13f79535-47bb-0310-9956-ffa450edef68
Fixed master to consolidate tasks upon slave re-registration.

Review: https://reviews.apache.org/r/10724

git-svn-id: https://svn.apache.org/repos/asf/incubator/mesos/trunk@1476341 13f79535-47bb-0310-9956-ffa450edef68
Fixed the slave to do disk usage calculations on the filesystem on
which the slave work directory is mounted.

Review: https://reviews.apache.org/r/10661

git-svn-id: https://svn.apache.org/repos/asf/incubator/mesos/trunk@1476345 13f79535-47bb-0310-9956-ffa450edef68
Simplify os::hostname() in libstout.
Run Hadoop tutorial binaries from within build dir.
Include pre/post-package hook scripts in Hadoop tutorial.
Allow ending Hadoop tutorial early.

Allow someone to end tutorial after building/packaging complete.  You
can also skip the test part by exporting SKIP_TESTS (i.e., 'make hadoop
SKIP_TESTS=1').
Use XZ (LZMA) for package on Linuxes.
Build fix for HadoopPipes.cc with GCC 4.7.
Check for Python.h in configure script.
Use more portable paths for tutorial test.
Don't prematurely kill TaskTrackers.

We wait for 300,000ms (5 minutes) of inactivity before we kill a running
TaskTracker in case there are still reducers who need the task results.

You may override the timeout by setting the number of milliseconds in
mapred-site.xml with the property 'mapred.tasktracker.idle.timeout'.
Improve MesosScheduler for Hadoop.

We'll try to allocate map/reduce slots in such a way that we ensure we
utilize the entire cluster effectively.  We'll use up to the maximum
desired number of map/reduce slots, starting from a minimum of 1 map or
1 reduce slot.
Hadoop tutorial version bump (CDH4.2.0 -> 4.2.1).
Shuffle offers before sending to frameworks.

This helps ensure fair allocation of resources.