(PUP-2214) Change doc application to use current environment
(PUP-2214) Change parser application to use current_environment

This changes the parser face to use the current_environment instead
of looking up the "configured environment" from settings and then
using that environment.

This also adjust the documentation for the command wrt. use
with --parser future.
(PUP-2214) Change node/clean face to use configured environment
(PUP-2214) Fix failing doc tests

Doc tests with mocking did not work, needed to use a real configured
env.
(PUP-2214) Add comment that node.environment is source of environment

This note is to ensure the lookup of :environment is not changed
to a lookup of :current_environment, since the node's environment
is what is used to determine what the current_environment should be.
(PUP-2014) Make module use current_environment

Module now uses current environment instead of configured
environment when being asked for a module and not supplying
an explicit environment name. It used to lookup to configured
environment giving invoking logic no chance to modify the
default without modifying the setting.
(PUP-2214) Make util rdoc and related parser use :current_environment
(PUP-2214) Add comment about looking up environment for requests.
(PUP-2214) Change autoloader to use current_environment for changed?

This changes the autoloader to use the current_environment as the
environment when performing a changed? operation. (It used to check
if the configured environment was changed).

The complicated bootstrap support still uses lookup of configured
environment as that is the fallback when booting.
(PUP-2214) Add comment what command_line "current_environment" means
(PUP-2214) Add comment about application's use of configured env
(PUP-2214) Add comment about module_tool's lookup of requested env
(PUP-2214) Remove dead environment method from rest indirector

Removing a private method for looking up the environment from the Rest
indirector becaues it does not seem to be called anymore.
(PUP-2214) Fix spec failures under 1.8.7

Fixes some rdoc1 spec issues by providing explicit envs in the specs.
Merge pull request #2631 from hlindberg/pup-2214_change-env-lookup-to-current-env

(PUP-2214) change env lookup to current env