Updated with last working copy of build_perl_modules used by Opsview
Use own variable instead of ENV
Merge branch 'hw/update-pm'

* hw/update-pm:
  Use own variable instead of ENV
  Updated with last working copy of build_perl_modules used by Opsview

Conflicts:
	tools/build_perl_modules
Remove the outdated "command.cfg" file
Remove "contrib" plugins

These days, sites such as "Nagios Exchange" are a much better place for
publishing plugins not maintained by the Plugins Development Team.