Cross-platform udevadm_settle

RHEL doens't have /sbin/udevadm. Call /sbin/udevsettle instead.
Use native method instead of shelling out
Fix typo in comment
Use df's POSIX output format

so that a mount point doesn't go to multiple lines
Prefer Bosh::Exec when shelling out
remove trivial whitespace
Merge pull request #50 from drnic/remove_trivial_whitespace

remove trivial whitespace
use sigar instead of sys-filesystem
Don't reuse dns_info_record (fix for recreating jobs)

This change prevents to reuse the stored dns_info_record, so it will
return the info fetched from the latest agent get_state call.

When recreating a job, instance updater tries to guess what changes
are needed to apply before recreating the vm. If we store the dns
info into an instance variable and later, when we delete/create
the vm again, there's a change in its IP address, dns record will
return the older IP address instead of the new one.
Merge 'origin/master' into rhel-agent

Conflicts:
	bosh_agent/lib/bosh_agent/message/disk.rb

Change-Id: Ic3afa9761a4fa433e11155adabb05950c9946365
updated badges in README

- only show master build in travis
- show new code climate badge
Merge pull request #35 from anfernee/rhel-agent

Some necessary changes that make agent runnable on rhel
Changed director job template to use new style properties in bosh/release

[Closes #40556779]
Support fast failure and skipping SSH tests in BAT via environment variables
Update BAT README with new BAT environment options
Better message when deleting unnamed instance
include original config in receipt

also modifies commands that take a receipt to not take the config file
too
fixed bugs in stemcell creation
make AMIs public in CI
make AZs configurable in the default spec template