change recommendation to local installation of rollup-watch (#1082)

bin/src/handleError.js

@@ -38,7 +38,7 @@ const handlers = {
 	},
 
 	ROLLUP_WATCH_NOT_INSTALLED: () => {
-		stderr( chalk.red( 'rollup --watch depends on the rollup-watch package, which could not be found. You can install it globally (recommended) with ' ) + chalk.cyan( 'npm install -g rollup-watch' ) );
+		stderr( chalk.red( 'rollup --watch depends on the rollup-watch package, which could not be found. Install it with ' ) + chalk.cyan( 'npm install -D rollup-watch' ) );
 	},
 
 	WATCHER_MISSING_INPUT_OR_OUTPUT: () => {

bin/src/runRollup.js

@@ -193,7 +193,7 @@ function execute ( options, command ) {
 
 				watcher.on( 'event', event => {
 					switch ( event.code ) {
-						case 'STARTING':
+						case 'STARTING': // TODO this isn't emitted by newer versions of rollup-watch
 							stderr( 'checking rollup-watch version...' );
 							break;