Implement new command to manage extension bundles

[liliankasem]

• Implement func bundle download command
• Implement func bundle list command
• Implement func bundle path command (this already exists, just need to redirect to this new command path)

[manvkaur]

Can this have an option to specify bundle id, similar request here to enable initialisation and use of preview bundle
#4436
func init --bundleId=preview
func new --bundleId=preview

[liliankasem]

The design for the download command is to install whatever is defined in your host.json, so the propsoed flag for func init --bundleId=preview should already initialize the version you intent on downloading