Add sanity checking to the whisper cli utilities

This isn't all inclusive, but is a good start
Properly handle SIGPIPE from whisper cli utils

Example reproducer:

$ whisper-create.py 1.wsp 1m:100d 1h:1y
Created: 1.wsp (1833160 bytes)
$ whisper-dump.py 1.wsp | head
Meta data:
  aggregation method: average
  max retention: 31536000
  xFilesFactor: 0.5

Archive 0 info:
  offset: 40
  seconds per point: 60
  points: 144000
  retention: 8640000
Traceback (most recent call last):
  File "./whisper-dump.py", line 91, in <module>
    dump_archives(header['archives'])
  File "./whisper-dump.py", line 84, in dump_archives
    print '%d: %d, %10.35g' % (point, timestamp, value)
IOError: [Errno 32] Broken pipe

After applying this patch:

$ whisper-create.py 1.wsp 1m:100d 1h:1y
Created: 1.wsp (1833160 bytes)
$ whisper-dump.py 1.wsp | head
Meta data:
  aggregation method: average
  max retention: 31536000
  xFilesFactor: 0.5

Archive 0 info:
  offset: 40
  seconds per point: 60
  points: 144000
  retention: 8640000
whisper-resize.py: gracefully handle bogus filenames
Another cleanup for bogus filenames
whisper-dump.py: Handle bogus files
whisper-merge.py: Handle bogus files
rrd2whisper.py: Handle bogus files
Merge pull request #2 from SEJeff/whisper-cli-cleanups

Whisper cli cleanups
Fix typo in error message

Closes https://bugs.launchpad.net/graphite/+bug/1007893
Dont dump out datapoints updated to stdout
Add option to aggregate values on resize

Via jens-rantil

Closes https://code.launchpad.net/~jens-rantil/whisper/whisper/+merge/105582
Add support for tox (http://tox.testrun.org/)
Add .travis.yml for Travis CI (http://travis-ci.org/)
Merge pull request #3 from msabramo/testing

Testing with tox and Travis CI
use max() instead of sorted()[-1]
Merge pull request #4 from AccelerationNet/master

Use max() where it makes sense
add fallocate support (by param) to whisper
Fix rhel5 / python2.4 mmap error

Running whisper-dump on RedHat 5 produces the following error:

Traceback (most recent call last):
  File "/usr/bin/whisper-dump.py", line 84, in ?
    map = mmap_file(path)
  File "/usr/bin/whisper-dump.py", line 19, in mmap_file
    map = mmap.mmap(fd, 0, prot=mmap.PROT_READ)
EnvironmentError: [Errno 22] Invalid argument

Which can be fixed by supplying an explicit size to the mmap call.
correct sparse allocation offset
Merge pull request #8 from snore/master

Fix whisper-dump.py with older mmap api