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/sys/hop.go

@@ -1,14 +1,14 @@
 package sys
 
 import (
-	"github.com/versenilvis/iris/commands/core"
+	"github.com/versenilvis/iris/spec"
 )
 
 func init() {
-	core.Register(&core.Spec{
+	spec.Register(&spec.Spec{
 		Name:        "hop",
 		Description: "Interact with Hop in your terminal",
-		Subcommands: []core.Subcommand{
+		Subcommands: []spec.Subcommand{
 			{Name: "auth", Description: "Authenticate with Hop"},
 			{Name: "help", Description: "Prints this message or the help of the given subcommand(s)"},
 			{Name: "login", Description: "Login to Hop"},
@@ -24,7 +24,7 @@ func init() {
 			{Name: "switch", Description: "Switch to a different project"},
 			{Name: "whoami", Description: "Get information about the current user"},
 		},
-		Options: []core.Option{
+		Options: []spec.Option{
 			{Name: "--type", Description: "Type of the container, defaults to `ephemeral`"},
 			{Name: "--containers", Description: "Number of containers to use, defaults to 1 if `scaling` is manual"},
 			{Name: "--cpu", Description: "The number of CPUs to use, defaults to 1"},