truffle help command executes command

[HaleTom]

Issue

Running truffle help <command> doesn't provide help, but instead runs the command.

This may run a command which the user didn't want to run, but simply to get help about.

Steps to Reproduce

$ truffle help help version help help
Truffle v3.4.11 (core: 3.4.11)
Solidity v0.4.15 (solc-js)

Expected Behavior

The help for the command is printed, the command is not run.

I'd expect to see:

Truffle v3.4.11 - a development framework for Ethereum

Usage: truffle <command> [options]
  version   Show version number and exit

See more at http://truffleframework.com/docs

Ideally, I'd see the applicable options listed for the command.

Actual Results

As above.

Environment

• Operating System: Linux svelte 4.9.52-1-MANJARO #1 SMP PREEMPT Wed Sep 27 16:40:38 UTC 2017 x86_64 GNU/Linux
• Truffle version: As above
• Ethereum client: N/A
• node version: v8.5.0
• npm version: 5.3.0

[HaleTom]

Duplicate of #618. My web browser misbehaved.