Better build process (#1248)

* Remove gulp, replace with custom scripts
* Symlink entire dirs where possible (fixes #1232)
* Significantly speed up subsequent builds (fixes #1238)
* Watch process now observes new/removed files, not only changed
* Add ignoreMask, exclude all files with names starting with a #
* Better logging during builds
* Update travis.yml to use new, non-gulp-based build

scripts/build.js

@@ -0,0 +1,44 @@
+const colors = require('colors/safe');
+
+const getBrowserify = require('./browserify');
+const getCopy = require('./copy');
+const getJS = require('./js');
+const getSass = require('./sass');
+const getSymlinks = require('./symlinks');
+const { formatDirsForMatcher, getSignatures, writeSignatures, cleanUp, onSuccess, onError} = require('./utils');
+const { dirs, symlinkDirs, copyDirs, symlinkFiles, jsFiles, ignoreMask } = require('./config');
+
+if (require.main === module) {
+	(async () => {
+		try {
+			const t1 = Date.now();
+			global.isError = false; // used to prevent further output to avoid concealing errors
+			const symlinks = symlinkFiles
+				.concat(dirs.map(d => `${d}/**`))
+				.concat([`!${formatDirsForMatcher(dirs)}/**/*.js`])
+				.concat([`!${formatDirsForMatcher(copyDirs)}/**`])
+
+			const signatures = await getSignatures();
+			const results = await Promise.all([
+				getBrowserify(signatures),
+				getCopy(copyDirs.map(d => `${d}/**`), { ignore: ignoreMask }, signatures),
+				getJS(jsFiles, { ignore: ignoreMask }, signatures),
+				getSass('scss/*.scss', { root: 'scss', ignore: ignoreMask }, signatures),
+				getSymlinks(symlinks, { nodir: true, ignore: ignoreMask }, signatures),
+				getSymlinks(symlinkDirs, { ignore: ignoreMask }, signatures),
+				cleanUp(signatures)
+			]);
+
+			await writeSignatures(signatures);
+			for (const result of results) {
+				onSuccess(result);
+			}
+			const t2 = Date.now();
+			console.log(colors.yellow(`Total build time ${t2 - t1}ms`));
+		} catch (err) {
+			process.exitCode = 1;
+			global.isError = true;
+			onError(err);
+		}
+	})();
+}