Refactor snapshot build (#2825)

Instead of using core/snapshot_creator.rs, instead two crates are
introduced which allow building the snapshot during build.rs.

Rollup is removed and replaced with our own bundler. This removes
the Node build dependency. Modules in //js now use Deno-style imports
with file extensions, rather than Node style extensionless imports.

This improves incremental build time when changes are made to //js files
by about 40 seconds.

1 files changed, 5 insertions, 5 deletions

diff --git a/js/net.ts b/js/net.ts
index 809dd4092..b0651b326 100644
--- a/js/net.ts
+++ b/js/net.ts
@@ -1,9 +1,9 @@
 // Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
-import { EOF, Reader, Writer, Closer } from "./io";
-import { notImplemented } from "./util";
-import { read, write, close } from "./files";
-import * as dispatch from "./dispatch";
-import { sendSync, sendAsync } from "./dispatch_json";
+import { EOF, Reader, Writer, Closer } from "./io.ts";
+import { notImplemented } from "./util.ts";
+import { read, write, close } from "./files.ts";
+import * as dispatch from "./dispatch.ts";
+import { sendSync, sendAsync } from "./dispatch_json.ts";
 
 export type Network = "tcp";
 // TODO support other types: