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/starkli.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:        "starkli",
 		Description: "Starkli, a ⚡ blazing ⚡ fast ⚡ CLI tool for Starknet powered by 🦀 starknet-rs 🦀",
-		Subcommands: []core.Subcommand{
+		Subcommands: []spec.Subcommand{
 			{Name: "account", Description: "Account management commands"},
 			{Name: "fetch", Description: "Fetch account config from an already deployed account contract"},
 			{Name: "ADDRESS", Description: "Contract address"},
@@ -59,7 +59,7 @@ func init() {
 			{Name: "transaction", Description: "Get Starknet transaction by hash"},
 			{Name: "transaction-receipt", Description: "Get transaction receipt by hash"},
 		},
-		Options: []core.Option{
+		Options: []spec.Option{
 			{Name: "--rpc", Description: "Starknet JSON-RPC endpoint"},
 			{Name: "--network", Description: "Starknet network"},
 			{Name: "--force", Description: "Overwrite the file if it already exists"},