Walking the dependency graph for all selected runtimes

Defaults to svr50 if no runtimes are specified
Modify the default dll search paths when we CORECLR_DIR is specified.
Made KPM pack work for full paths
- Changed Microsoft.Framework.PackageManager to be a class lib
- Use the file name when resolving the target framework

#166
build install will start new command window using built KRE

requires kvm on path
also sets 'build' alias to built version
Removing install command

It was only ever there to help test cmdline parsing
Will come back eventually
Adding --appfolder <NAME> switch to kpm pack

Changes the primary project's folder name in the output location
One commonly usage is "--appfolder wwwroot"
Is single folder name only, must not be a path
Copy fewer files when packing

see #182
Clear ReadOnly attribute from file as copied

See #196
Updating kproj file to match tooling changes
Added bash scripts to mono package
Made package restore work on mono (again)
- Use WindowsBase where ZipArchive is being used
Reworked error handling logic
- Show exception message when running from a console host
- Set KRE_CONSOLE_HOST=1 when running from klr.exe or mono host
- Create specific exception for compile errors (CompilationException)
- Show better errors from the ApplicationHost when loading the entrypoint fails
Set the exception message for the CompilationException
Made changes to the build
- Made it so that there is a folder per package
  in artifacts build.

#153
Fix handling of empty item in source file pattern list