allow external modules to be specified via CLI

bin/help.md

@@ -10,6 +10,7 @@ Basic options:
 -i, --input              Input (alternative to <entry file>)
 -o, --output <output>    Output (if absent, prints to stdout)
 -f, --format [umd]       Type of output (amd, cjs, es6, iife, umd)
+-e, --external           Comma-separate list of module IDs to exclude
 -n, --name               Name for UMD export
 -u, --id                 ID for AMD module (default is anonymous)
 -m, --sourcemap          Generate sourcemap (`-m inline` for inline map)

bin/index.js

@@ -12,7 +12,8 @@ command = minimist( process.argv.slice( 2 ), {
 		f: 'format',
 		m: 'sourcemap',
 		n: 'name',
-		u: 'id'
+		u: 'id',
+		e: 'external'
 	}
 });
 

bin/runRollup.js

@@ -34,7 +34,8 @@ function bundle ( options, method ) {
 	}
 
 	return rollup.rollup({
-		entry: options.input
+		entry: options.input,
+		external: options.external && options.external.split( ',' )
 	}).then( function ( bundle ) {
 		var generateOptions = {
 			dest: options.output,