(PUP-2303) Fix arguments of ArgumentError

Yo dawg, I heard you like ArgumentErrors so I put an
ArgumentError in your ArgumentError.

This makes errors in fileserver config much more readable and
easier to find.
(PUP-2240) Add unfold of array using splat unary * operator

This adds the ability to unfold values into individual parameters
and entries in lists the same way as this is done in Ruby.
(PUP-2240) Fix failing test (hash order ruby 1.8.7)
(maint) Remove calls to removed function

On master, the extra check if a function was available before evaluating
arguments was removed. The rebased code still had this call.
(PUP-2287) Fix lambda param with default is always choosen

This fixes the problem that a lambda parameter with a default always
was choosen even if a value was given for the parameter.

The expected behavior for function calls is that only truly missing (non
given) arguments are subjects to default value replacement, not if a
value is nil or undef. (This because functions are call by position, and
not call by name as for defines and classes). Thus all nil/undef values
are treated as any other value.

One test for the map function relied on the now fixed bug and it has
been marked pending, as it should be updated once the map function has
been transitioned to the new function API. (Where undef is not
transformed to empty string).
(maint) Update test using old style initialization of loaders

The API for creating loaders was changed (now requiring an environment).
This updates the logic that used the old API.
(PUP-2369) Add class to the message we return.

Add the class of the values we're changing from and to in the message
that's being returned. At the very least this will give developers a
hint about the types they're comparing explaining possible weird
behaviour.
(doc) Improve description of certname setting

This commit mentions our recommendations for certname values, as well as the one
reserved certname of `ca`. It also adds some context about what the certname is
used for.
(doc) Improve description of recurse, recurselimit, and purge attributes

The file type's `recurse` attribute didn't really explain what it did, and
didn't accurately describe the difference between `true` and `remote`. This
commit clears that all up.
(doc) Exec type: Clarify that onlyif/unless use exit codes, not stdout

This commit also clarifies that they use the same provider as the main command.
(doc) List order of log levels in description of the loglevel metaparameter
(doc) List allowed log levels in description of the log_level setting
(PUP-2010) have test repos pushed to hosts during acceptance testing

This patch changes the logic of how test packages are installed on SUTs.
Currently, repo packages are pulled by the individual SUTs - this works
because we assume that the SUTs are located within the Puppet Labs
network and can access builds.puppetlabs.lan. To run acceptance tests
in the cloud the workflow needs to be changed to have the test packages
pushed to the SUTs by the jenkins master node.

Tested successfully on jenkins, also updated spec tests.

This code relies on Beaker 1.8+ DSL methods.
(doc) Document key purging in the description of the ssh_authorized_key type

This commit puts an explanation of key purging over where people will likely be
looking for it. It also tightens up the description of the user type's
purge_ssh_keys attribute, and adds an example key to the ssh_authorized_key type
(since the way that type breaks up key lines is somewhat unintuitive).

The example public key is a dud, to prevent accidental access grants.
(doc) Update package provider descriptions for install/uninstall options support.

Updating package provider descriptions to document support for install_options and uninstall_options.
(docs) Fix wording on environment_timeout setting

Including the AS_DURATION snippet (which is a complete sentence) midway through
a sentence results in wacky wording. This commit fixes it.
(maint) Print yard error message to STDERR, not STDOUT

As this is an error/warning, the output should be put to STDERR instead
of STDOUT so it can be easily filtered.
(PUP-2311) OpenBSD uninstall broken when multiple uninstall_options given
(PUP-2458) Tests for providers inheriting from providers of another type

It's sometimes desirable to create new providers that inherit from providers
of a different type to create more specialised types/providers from a common
base.  This adds tests around this already-present functionality.
(PUP-957) Remove special meaning of Regexp[r] in =~ !~ expressions.

There are several issues with the previously implemented support
where a parameterized Regexp was a stand in for a real regular
expression:
* The match variables where not set (and would be difficult to return
  in general since Regexp's and Patterns can be nested in other types).
* Blurry line between what a Regexp type is, and String since Regexp[r]
produces a RegularExpression Type, not a Regexp instance.

This simply removes the special handling. A user can still use:

* Regexp (/..../)
* A String - transforms to a Regexp
* Pattern[p] type (since it is a real subtype of String)