build out cli and add size and gather functionality

cmd/cli/flags.go

@@ -0,0 +1,12 @@
+package main
+
+import "github.com/urfave/cli/v2"
+
+func baseDirFlag() *cli.StringFlag {
+	return &cli.StringFlag{
+		Name:    "baseDir",
+		Usage:   "The base directory to gather info from",
+		Aliases: []string{"b"},
+		Value:   ".",
+	}
+}