v0.0.55: Licence agreement change fix

Fixes #191, whereby acmetool did not correctly respond to changes in an
ACME server's preferred agreement. This is an important update and should
be applied promptly, as it causes autorenewal to fail (though by design,
acmetool requires intervention to agree to new agreements anyway).

Implements new option as per #178, where HTTP self-testing
can be disabled.

Fixes #186, whereby there is a small chance of a DNS
token string being interpreted as an option to grep in
the example DNS hook included in the repository.

The dependency on degoutils has been removed in favour
of a marginally more stable version.

Fixes #175, whereby HAProxy symlinks are now forcibly replaced.

Fixes #171, whereby the haproxy directory could be created
world-readable in some circumstances.

Miscellaneous release engineering changes related to changes
in boulder.

v0.0.54

v0.0.54: Add support for packaging for older RPM distros

v0.0.53

v0.0.53: Enable copr builds for Fedora 24

v0.0.52: Fix minor bugs

Fixes a minor bug where if a response file contained an invalid e. mail
address, acmetool would loop forever.

Fixes a minor bug where state and hook directory paths would be interpreted
incorrectly if they were specified as relative paths.

v0.0.51: Fix for minor resource consumption vulnerabilities

This release fixes minor resource consumption vulnerabilities which are mostly
academic. They can only be exploited by an ACME server.

v0.0.50: Minor changes

acmetool now sets umask to 0 on launch, to ensure that webroot
files can be written world-readable.

Changed back to using cheggaaa/pb rather than branch, now that
changes have been merged upstream.

Responder listen addresses are now intelligently sorted.

CSRs now contain a CN, which is the first name specified in
a target, which can help ensure that that name ends up as the
CN in the final certificate.

Fixed typos.

The Ubuntu(/Debian) PPA now provides arm and arm64 builds.
These should work on ARM platforms with and without hardfloat support.

v0.0.49: Bugfixes

Builds are now made using Go 1.6.

The quickstart wizard no longer tries and fails to install a cronjob if a means
of installation cannot be found.

A bug causing the redirector to fail to launch has been fixed.

In acmeapi, HTTPError is now exported to allow the examination of errors.

The log message severity for a failure to save webroot files is now Info,
which prevents the emission of annoying error messages in cron jobs
when not running as root.

v0.0.48: Minor fixes

A 'conceivably satisfiable' check has been added to ensure a target's request section can conceivably satisfy
the satisfy section.

The renewal period has been reverted back to 30-days-or-33%, since Let's
Encrypt is sending renewal e. mails at 20 days.

v0.0.47: Add experimental cull command

Fix FDB bugs.

v0.0.46: Add support for TLS-SNI hooks; combined certificate file reform

The HAProxy hook is now rebranded as the combined certificate file hook.

lighttpd is now considered a daemon which needs combined files.

TLS-SNI code cleaned up, support for 'n' removed now that it has been
removed from the ACME specification. TLS-SNI challenges can now
be met using hooks.

Fixed a bug where quickstart didn't pass --hooks to crontab if --hooks
was specified on the command line.

Allow FDB permissions customization to specify UID without specifying GID and
vice versa.