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/minikube.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:        "minikube",
 		Description: "Format to print stdout in",
-		Subcommands: []core.Subcommand{
+		Subcommands: []spec.Subcommand{
 			{Name: "start", Description: "Starts a local Kubernetes cluster"},
 			{Name: "status", Description: "Gets the status of a local Kubernetes cluster"},
 			{Name: "stop", Description: "Stops a running local Kubernetes cluster"},
@@ -60,7 +60,7 @@ func init() {
 			{Name: "completion", Description: "Generate command completion for a shell"},
 			{Name: "bash", Description: "Bash completion"},
 		},
-		Options: []core.Option{
+		Options: []spec.Option{
 			{Name: "--output", Description: "Format to print stdout in"},
 			{Name: "--shell", Description: "Force environment to be configured for a specified shell"},
 			{Name: "--unset", Description: "Unset variables instead of setting them"},