Add user prompts

Fixes #106

cmd/root.go

@@ -54,9 +54,31 @@ var (
 
 // RootCmd represents the base command when called without any subcommands
 var RootCmd = &cobra.Command{
-	Use:     "luet",
-	Short:   "Package manager for the XXth century!",
-	Long:    `Package manager which uses containers to build packages`,
+	Use:   "luet",
+	Short: "Package manager for the XXth century!",
+	Long: `Luet is a single-binary package manager based on containers to build packages.
+	
+To install a package:
+
+$ luet install package
+
+To search for a package in the repositories:
+
+$ luet search package
+
+To list all packages installed in the system:
+
+$ luet search --installed .
+
+To show hidden packages:
+
+$ luet search --hidden package
+
+To build a package, from a tree definition:
+
+$ luet build --tree tree/path package
+	
+`,
 	Version: fmt.Sprintf("%s-g%s %s", LuetCLIVersion, BuildCommit, BuildTime),
 	PersistentPreRun: func(cmd *cobra.Command, args []string) {
 		err := LoadConfig(config.LuetCfg)