fixed compacting swallowing blank lines within template literals

this is a workaround until rollup-plugin-cleanup has been fixed:
aMarCruz/rollup-plugin-cleanup#7

Author: FND

lib/bundle/config.js

@@ -78,7 +78,7 @@ function generateConfig({ extensions = [], externals, format, moduleName,
 	]);
 	if(compact) {
 		let cleanup = require("rollup-plugin-cleanup");
-		plugins = plugins.concat(cleanup());
+		plugins = plugins.concat(cleanup({ maxEmptyLines: -1 }));
 	}
 
 	let cfg = { format, plugins };

test/unit/fixtures/src/multiline.js

@@ -0,0 +1,5 @@
+let txt = `foo
+
+bar`;
+
+console.log(`[…] ${txt}`); // eslint-disable-line no-console

test/unit/test_bundling.js

@@ -303,7 +303,7 @@ console.log(\`[…] $\{util}\`); // eslint-disable-line no-console
 
 	it("should optionally compact bundle", () => {
 		let config = [{
-			source: "./src/index.js",
+			source: "./src/multiline.js",
 			target: "./dist/bundle.js"
 		}];
 		let assetManager = new MockAssetManager(FIXTURES_DIR);
@@ -314,9 +314,11 @@ console.log(\`[…] $\{util}\`); // eslint-disable-line no-console
 				assetManager.assertWrites([{
 					filepath: path.resolve(FIXTURES_DIR, "./dist/bundle.js"),
 					content: makeBundle(`
-var util = "UTIL";
+let txt = \`foo
+
+bar\`;
 
-console.log(\`[…] $\{util}\`);
+console.log(\`[…] $\{txt}\`);
 					`.trim())
 				}]);
 
@@ -328,9 +330,9 @@ console.log(\`[…] $\{util}\`);
 				assetManager.assertWrites([{
 					filepath: path.resolve(FIXTURES_DIR, "./dist/bundle.js"),
 					content: makeBundle(`
-var util = "UTIL";
+var txt = "foo\\n\\nbar";
 
-console.log("[\\u2026] " + util);
+console.log("[\\u2026] " + txt);
 					`.trim())
 				}]);
 
@@ -342,9 +344,9 @@ console.log("[\\u2026] " + util);
 				assetManager.assertWrites([{
 					filepath: path.resolve(FIXTURES_DIR, "./dist/bundle.js"),
 					content: makeBundle(`
-var util = "UTIL";
+var txt = "foo\\n\\nbar";
 
-console.log("[\\u2026] " + util); // eslint-disable-line no-console
+console.log("[\\u2026] " + txt); // eslint-disable-line no-console
 					`.trim())
 				}]);
 			});