When the dotnet host is run without any arguments, it should display proper help

Steps to reproduce

dotnet

Expected behavior

See something along the lines of the following:

.NET Command Line Tools (1.0.0-preview1-002702)
Usage: dotnet [common-options] [command] [arguments]
Run your application: dotnet [path to your assembly.dll]

Arguments:
  [command]     The command to execute
  [arguments]   Arguments to pass to the command

Common Options (passed before the command):
  -v|--verbose  Enable verbose output
  --version     Display .NET CLI Version Number
  --info        Display .NET CLI Info

Common Commands:
  new           Initialize a basic .NET project
  restore       Restore dependencies specified in the .NET project
  build         Builds a .NET project
  publish       Publishes a .NET project for deployment (including the runtime)
  run           Compiles and immediately executes a .NET project
  test          Runs unit tests using the test runner specified in the project
  pack          Creates a NuGet package

Actual behavior

See the following:

Usage: dotnet [--help | app.dll]

Environment data

dotnet --info output:

.NET Command Line Tools (1.0.0-preview1-002702)

Product Information:
 Version:     1.0.0-preview1-002702
 Commit Sha:  6cde21225e

Runtime Environment:
 OS Name:     Mac OS X
 OS Version:  10.11
 OS Platform: Darwin
 RID:         osx.10.11-x64

/cc @piotrpMSFT @schellap @eerhardt @shanselman @richlander

[schellap]

Btw, I like your less clutter.

[richlander]

Hmmm … I can see that I had a flaw in my thinking. I was think the same info would be available via dotnet --version but didn’t actually check that assumption. Bad plan. I can also guess that there are tools that will check the version via that command and it would be bad to add more text there.

Alternate proposal:

Microsoft .NET Core Host - Version 1.0.1
Usage: dotnet [options] [path-to-application]

Options:
--help Display .NET Core Host help.
--version Display .NET Core Host version.
--fx-version .NET Core version to use to run the application.
--additionalprobingpath Path to use for probing policy and assembly probing.

Path to Application:
The path to a .NET Core managed application, dll or exe file to execute.

Set 'COREHOST_TRACE' to '1' to see tracing information.

Learn more about .NET Core: https://dot.net/core

Build: cee57bf6c981237d80aa1631cfe83cb9ba329f12

It’s not info that helps you with help, so it seems odd for two lines of version information to come at the top of the display. So, I propose to put the version info in the first line and add the Build commit in the last line. That seems like the value of the info is exactly commensurate with its placement.

On that note, what is the build SHA from? Which repo?