Add port/package URL for py-acme
Use Freshports URL's instead of SVNWeb (repository) links as they provide (binary) package installation installation as well as further port/package information such as vulnerabilities, revision history and bug reports for each port respectively.
1. Replace the outdated reference to "vritualenv", "see below" -> "see above".
2. Replace the awkward sentence (partially incorrect) about installing on FreeBSD.
It can be installed via different ways: "pkg" is not exclusive. I am not aware of any reason why it canNOT be installed from ports. Some people prefer build and install everything from ports. (The previous version of the description implies that ports cannot be used.)
Move "Writing your own plugin" under Code components and layout, with the other
plugin docs.
Include instructions on how to install a plugin into a virtualenv and how to check
for its presence.
Document that users can install third-party plugins systemwide, but not with
certbot-auto.
Remove obsolete information from Authenticators section and make the section
more informative.
Remove IDisplay sub-section since it repeats information in the main "Plugin
architecture" section.
* remove instructions about removed Vagrantfile
* rewrite docker instructions
* say where docker-compose can be run
* give better intro for macOS devs
* prompt people for permission to install OS packages
* reword awkward sentence
* Change WORKDIR to /opt/certbot/src
This change is OK because all paths used in Dockerfile-dev are absolute paths.
* remove 'cd src' instructions for Dockerfile-dev
* Improve docker-compose testing instructions
Correct tagging format.
Add request for random offsets for renewal.
Make all bulleted lists consistent.
Remove obsolete `letsencrypt` package for Fedora.
Remove discouraged letshelp-certbot package.
Recommend faster-running commands with clearer output first, building up to
slow, noisy, `tox` last.
Remove outdated Boulder testing advice, and outdated Boulder testing scripts
(Vagrantfile, mac-bootstrap.sh, boulder-start.sh). Update Boulder testing
section.
Fill out "directory structure" section of contributing guide a little better.
