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/netlify.go

@@ -1,18 +1,18 @@
 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:        "netlify",
 		Description: "Print debugging information",
-		Subcommands: []core.Subcommand{
+		Subcommands: []spec.Subcommand{
 			{Name: "help", Description: "List available sub-commands"},
 			{Name: "subcommand", Description: "The command to display help for"},
 		},
-		Options: []core.Option{
+		Options: []spec.Option{
 			{Name: "--debug", Description: "Print debugging information"},
 			{Name: "--httpProxy", Description: "Proxy server address to route requests through"},
 			{Name: "-f", Description: "Delete without prompting (useful for CI)"},