Maint: Update docs for schedule type and metaparameter

The wording of these was out of date and somewhat strange.
Maint: Improve/reduce documentation of relationship metaparemeters

These descriptions were too wordy and too inconsistent. I'm imposing a format on
them so they all look alike, and a casual reader can tell how many there are and
how their behaviors differ. I'm also adding links to the more detailed
documentation.
Maint: Standardize docs for refresh behavior in resource types; clarify exec docs

Service/mount/exec already documented that they do the refresh thing, but it
wasn't organized in a predictable way. I'm imposing a convention of a bold
"Refresh" label, a reminder of where events come from, and a description of what
that type does when it gets one.

This commit also adds a lot more detail on how execs respond to refresh, since
it's actually really complicated and not the least bit intuitive. I also reworded
some of the older language near the top of the exec type, while I was in there.
Maint: Clarify docs for stage type and metaparameter

This was pretty disorganized and confusing. Now it's less so!
(PUP-1218) Add ssh-ed25519 support to the sshkey type
(PUP-1218) Teach the ssh_authorized_key provider about ssh-ed25519 too.
PUP-1322 Do not fail hard on unparseable files
(PUP-1211) Force registry value encoding to match code page

Ruby uses ANSI versions of Win32 APIs to read values from the registry. The
encoding of these strings depends on the active code page. However, ruby
incorrectly sets the string encoding to US-ASCII.[1]

As a result, if you try to perform a regex match on the string, and the string
contains the registered trademark symbol, 0xAE, then ruby will raise an error
saying 'Invalid byte sequence in US-ASCII'

This commit forces the encoding of REG_SZ, REG_EXPAND_SZ, and REG_MULTI_SZ to
the encoding for the active code page. So if the active code page is 1252, the
ruby encoding will be `Encoding::CP1252`.

See https://bugs.ruby-lang.org/issues/8943
Merge pull request #2229 from joshcooper/issue/stable/PUP-1211-registry-encoding

(PUP-1211) Force registry value encoding to match code page
Merge pull request #2156 from nfagerlund/docs_metaparams_schedule

Docs: Schedule, stage, and other metaparams
(PUP-736) Remove description from RPM/DPKG

Encoding mis-match causes package prefetching to fail with
'invalid byte sequence in US-ASCII'. The guidelines for the
Debian Project [1] and the Fedora Project [2] specify that
metadata files should be UTF-8 encoded, but it is not
enforced.

Since we are not able to force encoding "UTF-8" to work around
this we have decided to back out the description from package
formats for now while working on a longer term solution for
encoding.

Without this fix the package formats fail if there is a package
with UTF-8 encoding in the description.

[1]: http://www.debian.org/doc/debian-policy/ch-controlfields.html
[2]: http://fedoraproject.org/wiki/Packaging:Guidelines#Encoding

Paired with Josh Partlow <joshua.partlow@puppetlabs.com>
(PUP-736) Do not test for package not found

And log unmatched lines at debug level. The executors for dpkg and rpm
will raise an error if the command line returns a non-zero status, which
it does for package not found errors.  This bypasses parsing and is
interpretted as package absent result.  Therefore there is no need to
attempt to parse 'package not found' and we can avoid any issues with
changing or translated messages.

If there are unrecognizable lines of output returned from a successful
execution, log them at debug level.  Logging at a warning level has the
potential to produce too much noise.

Dpkg#query is no longer multi-line output and no longer requires
filtering through a pipe.
(maint) Improve docs for acceptance ci:test:git from another FORK
(PUP-1151) Add documentation for environments endpoint
(PUP-1151) Specify JSON and error responses

We need to move away from PSON in puppet. Using V2 as a switching point
is as good as any. This also specifies how error responses are
formatted.
(PUP-1151) Have puppet depend on json

In order to have the v2 api emit and consume JSON puppet will need to
have access to a json library. This adds it to our dependencies for
debian, redhat, and gem packages. This should be a safe thing to do
since puppet already needs hiera and hiera depends on JSON, so this is
just taking the same dependency that hiera already had and applying it
directly to puppet.
(PUP-1151) Fix environment enumeration endpoint test
Merge pull request #2241 from aperiodic/pup-1151-environment-enumeration-test-fix

(PUP-1151) Fix environment enumeration endpoint test
(PUP-716) File19Windows#symlink calls exist? on instance not class.

Fixes a bug that was calling exist? on the File19Windows impl class when
it was now an instance method of the same.
Merge pull request #2242 from jpartlow/issue/master/pup-716-fix-exist-call-in-file19windows-impl

(PUP-716) File19Windows#symlink calls exist? on instance not class.