add_field_env property added.
Run Beaver with su for environment variables to become available.
Merge branch 'master' of https://github.com/rampire/cookbook-beaver into rampire-master

Conflicts:
	providers/tail.rb
	resources/tail.rb
Merge branch 'rampire-master'
Add contributors to `README.md`
Bump version to 1.3.0