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/space.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:        "space",
 		Description: "Deta Space CLI for mananging Deta Space projects",
-		Subcommands: []core.Subcommand{
+		Subcommands: []spec.Subcommand{
 			{Name: "completion", Description: "Generate the autocompletion script for the specified shell"},
 			{Name: "bash", Description: "Generate the autocompletion script for bash"},
 			{Name: "fish", Description: "Generate the autocompletion script for fish"},
@@ -25,7 +25,7 @@ func init() {
 			{Name: "upgrade", Description: "Upgrade Space CLI version"},
 			{Name: "help", Description: "Help about any command"},
 		},
-		Options: []core.Option{
+		Options: []spec.Option{
 			{Name: "--no-descriptions", Description: "Disable completion descriptions"},
 			{Name: "--dir", Description: "Src of project to link"},
 			{Name: "--id", Description: "Project id of project to link"},