refactor(commands): separate commands and its core into two folders (#32)

- I think it would be better if one for commands only, one for the spec
handling core logic so people won't be confused by the core logic inside
the commands folder (cleaner I guess)
- Regen docs

commands/ops/ngrok.go

@@ -1,14 +1,14 @@
 package ops
 
 import (
-	"github.com/versenilvis/iris/commands/core"
+	"github.com/versenilvis/iris/spec"
 )
 
 func init() {
-	core.Register(&core.Spec{
+	spec.Register(&spec.Spec{
 		Name:        "ngrok",
 		Description: "Path to log file,",
-		Subcommands: []core.Subcommand{
+		Subcommands: []spec.Subcommand{
 			{Name: "help", Description: "Shows a list of commands or help for one command"},
 			{Name: "authtoken", Description: "Save authtoken to configuration file"},
 			{Name: "credits", Description: "Prints author and licensing information"},
@@ -20,7 +20,7 @@ func init() {
 			{Name: "version", Description: "Print the version string"},
 			{Name: "8080", Description: "Port"},
 		},
-		Options: []core.Option{
+		Options: []spec.Option{
 			{Name: "--all", Description: "Start all tunnels in the configuration file"},
 			{Name: "--none", Description: "Start running no tunnels"},
 			{Name: "--remote-addr", Description: "Bind remote address (requires you reserve an address)"},