(QENG-989) install_puppet_from_gem fails on Solaris

Trying to install puppet from gems would fail on both Solaris 10 and
11. Solaris 10 now has pkgutil and gem symlinked (ln -s) to /usr/bin.
Both Solaris versions have puppet-related gems symlinked to /usr/bin
after installation. This is to avoid clobbering the PATH.
Merge pull request #440 from colinPL/qeng989_solaris_gem

(QENG-989) install_puppet_from_gem fails on Solaris
(MAINT) broken spec fixes (docker + copy_module_to)

- docker spec was still allowing sleeps to execute making things run
  slow
- update copy_module_to spec test to use correct ignore list
Merge pull request #451 from anodelman/maint

(MAINT) broken spec fixes (docker + copy_module_to)
(QENG-526) A friendly way for Beaker to set environment...

... variables for SUTs

- add support for option :host_env, it can be set in the host
  configuration file
- requires updating each host so that sshd allows remotely setting
  environment variables
- add host.add_env_var(key,val) and host.delete_env_var(key,val) for
  using in test writing