Added @doc false to terminate and code_change
Use setlocal/endlocal to prevent polluting user's environment
Use start to spawn werl without lingering cmd window
Suppress "dumb terminal" warning
Add new --werl option
Merge pull request #2573 from chyndman/iex-werl-option

Windows IEx enhancements
Merge pull request #2592 from tomkadwill/doc-false

Added @doc false to terminate and code_change