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/view/idea.go

@@ -1,20 +1,20 @@
 package view
 
 import (
-	"github.com/versenilvis/iris/commands/core"
+	"github.com/versenilvis/iris/spec"
 )
 
 func init() {
-	core.Register(&core.Spec{
+	spec.Register(&spec.Spec{
 		Name:        "idea",
 		Description: "IntelliJ IDEA CLI",
-		Subcommands: []core.Subcommand{
+		Subcommands: []spec.Subcommand{
 			{Name: "diff", Description: "Open the diff viewer to see the differences between two specified files"},
 			{Name: "merge", Description: "Open the Merge dialog to merge the specified files"},
 			{Name: "format", Description: "Apply code style formatting to the specified files"},
 			{Name: "inspect", Description: "Perform code inspection on the specified project"},
 		},
-		Options: []core.Option{
+		Options: []spec.Option{
 			{Name: "-h", Description: "Show help for format command"},
 			{Name: "-m", Description: "Process specified directories recursively"},
 			{Name: "-s", Description: "Specify the code style settings file to use for formatting"},