Use a binary shim
Use node.exe shim

add local command
alias use to env
alias update to selfupdate
polish list to reflect global, local and env version
Update README
Add args command and recursive .node-version search
Document args command
Fix local .node-version recursion
Fix nodist#getPathToExe

would return v/undefined/node.exe
Merge branch 'shim'

Conflicts:
	.gitignore
	README.md
v0.5.0