dotnet-new csproj templates (#4382)

Make csproj templates first-class in dotnet-new.

TestAssets/TestProjects/ProjectJsonWebTemplate/gulpfile.js

@@ -0,0 +1,45 @@
+/// <binding Clean='clean' />
+"use strict";
+
+var gulp = require("gulp"),
+    rimraf = require("rimraf"),
+    concat = require("gulp-concat"),
+    cssmin = require("gulp-cssmin"),
+    uglify = require("gulp-uglify");
+
+var webroot = "./wwwroot/";
+
+var paths = {
+    js: webroot + "js/**/*.js",
+    minJs: webroot + "js/**/*.min.js",
+    css: webroot + "css/**/*.css",
+    minCss: webroot + "css/**/*.min.css",
+    concatJsDest: webroot + "js/site.min.js",
+    concatCssDest: webroot + "css/site.min.css"
+};
+
+gulp.task("clean:js", function (cb) {
+    rimraf(paths.concatJsDest, cb);
+});
+
+gulp.task("clean:css", function (cb) {
+    rimraf(paths.concatCssDest, cb);
+});
+
+gulp.task("clean", ["clean:js", "clean:css"]);
+
+gulp.task("min:js", function () {
+    return gulp.src([paths.js, "!" + paths.minJs], { base: "." })
+        .pipe(concat(paths.concatJsDest))
+        .pipe(uglify())
+        .pipe(gulp.dest("."));
+});
+
+gulp.task("min:css", function () {
+    return gulp.src([paths.css, "!" + paths.minCss])
+        .pipe(concat(paths.concatCssDest))
+        .pipe(cssmin())
+        .pipe(gulp.dest("."));
+});
+
+gulp.task("min", ["min:js", "min:css"]);