Fix "k --version" continues executing

parent #784 

Tested the following behaviors:
```
PS C:\Users\wwa\Documents\ProjectK\tmp\KRuntime> k
Usage: k [options] [command]

Options:
  --watch                          Watch file changes
  --packages <PACKAGE_DIR>         Directory containing packages
  --configuration <CONFIGURATION>  The configuration to run under
  --port <PORT>                    The port to the compilation server
  -?|-h|--help                     Show help information
  --version                        Show version information

Commands:
  run  Run application
PS C:\Users\wwa\Documents\ProjectK\tmp\KRuntime> echo $lastexitcode
2
PS C:\Users\wwa\Documents\ProjectK\tmp\KRuntime> k --help
Usage: k [options] [command]

Options:
  --watch                          Watch file changes
  --packages <PACKAGE_DIR>         Directory containing packages
  --configuration <CONFIGURATION>  The configuration to run under
  --port <PORT>                    The port to the compilation server
  -?|-h|--help                     Show help information
  --version                        Show version information

Commands:
  run  Run application
PS C:\Users\wwa\Documents\ProjectK\tmp\KRuntime> echo $lastexitcode
0
PS C:\Users\wwa\Documents\ProjectK\tmp\KRuntime> k --version
1.0.0-t141023235336
PS C:\Users\wwa\Documents\ProjectK\tmp\KRuntime> echo $lastexitcode
0
PS C:\Users\wwa\Documents\ProjectK\tmp\KRuntime> k --invalid
System.Exception: Unable to locate project.json
   at Microsoft.Framework.Runtime.DefaultHost.Initialize(DefaultHostOptions options, IServiceProvider hostServices)
   at Microsoft.Framework.Runtime.DefaultHost..ctor(DefaultHostOptions options, IServiceProvider hostServices)
   at Microsoft.Framework.ApplicationHost.Program.Main(String[] args)
PS C:\Users\wwa\Documents\ProjectK\tmp\KRuntime> echo $lastexitcode
1
```