Using the default value of 16 minutes (960 seconds) for
--dns-linode-propagation-seconds leads to DNS failures when the randomly
selected Linode DNS is not the first one out of six, due to an additional
delay before the other five are updated.
The problem can be easily solved by increasing the wait interval, so
this commit increases the default value to 20 minutes.
More details: https://community.letsencrypt.org/t/dns-servers-used-by-letsencrypt-for-challenges/32127/16
* Added DNS based authenticator plugin for Linode
* Added linode plugin to docs
* Added Dockerfile
* Added .gitignore and readthedocs.org.requirements.txt
* Updated default_propagation_seconds
* Updated according to changes requested
* Bump version to 0.26.0
* Advertise our packages work on Python 3.7.