Add README.md for package:fasta.

pkg/fasta/README.md

+<!--
+Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
+for details. All rights reserved. Use of this source code is governed by a
+BSD-style license that can be found in the LICENSE file.
+-->
+# Fasta -- Fully-resolved AST, Accelerated.
+
+Fasta is a compiler framework for compiling Dart sources to Kernel IR. When Fasta works well, you won't even know you're using it, as it will be transparently integrated in tools like *dart*, *dartanalyzer*, *dart2js*, etc.
+
+Hopefully, you'll notice that Fasta-based tools are fast, with good error messages. If not, please let us [know](https://github.com/dart-lang/sdk/issues/new).
+
+Fasta sounds like faster, and that's a promise we intend to keep.
+
+## Getting Started
+
+1. [Build](https://github.com/dart-lang/sdk/wiki/Building#building) the VM and patched SDK. Note: you only need to build the target `runtime`, so you only need to run this command:
+
+```bash
+./tools/build.py --mode release --arch ia32 runtime
+```
+
+Make sure to define these environment variables, for example, by adding them to `~/.bashrc`:
+
+```bash
+# Linux
+DART_SDK=<Location of Dart SDK source check out>
+export DART_AOT_VM=${DART_SDK}/out/ReleaseIA32/dart
+export DART_AOT_SDK=${DART_SDK}/out/ReleaseIA32/patched_sdk
+```
+
+```bash
+# Mac OS X
+DART_SDK=<Location of Dart SDK source check out>
+export DART_AOT_VM=${DART_SDK}/xcodebuild/ReleaseIA32/dart
+export DART_AOT_SDK=${DART_SDK}/xcodebuild/ReleaseIA32/patched_sdk
+```
+
+If you want to help us translate these instructions to another OS, please let us [know](https://github.com/dart-lang/sdk/issues/new).
+
+## Create an Outline File
+
+1. Run `dart pkg/fasta/bin/outline.dart pkg/compiler/lib/src/dart2js.dart`
+
+2. Optionally, run `dart pkg/kernel/bin/dartk.dart outline.dill` to view the generated outline.
+
+This will generate a file named `outline.dill` which contains a serialized reprsentation of the input program excluding method bodies. This is similar to an analyzer summary.
+
+
+## Create a Platform Dill File
+
+A `platform.dill` is a dill file that contains the Dart SDK platform libraries. For now, this is generated with dartk until fasta reaches a higher rate of test passes.
+
+```bash
+dart pkg/fasta/bin/compile_platform.dart platform.dill
+```
+
+Make sure to define `$DART_AOT_SDK` as described [above](#Building-The-Dart-SDK).
+
+## Compiling a Program
+
+```bash
+dart pkg/fasta/bin/compile.dart test/hello.dart
+```
+
+This will generate `program.dill` which can be run this way:
+
+```bash
+$DART_AOT_VM program.dill
+```
+
+Where `$DART_AOT_VM` is defined as described [above](#Building-The-Dart-SDK).
+
+### Using dartk and the Analyzer AST
+
+```bash
+dart pkg/fasta/bin/kompile.dart test/hello.dart
+```
+
+This will generate `program.dill` which can be run this way:
+
+```bash
+$DART_AOT_VM program.dill
+```
+
+Where `$DART_AOT_VM` is defined as described [above](#Building-The-Dart-SDK).
+
+## Running Tests
+
+Run:
+
+```bash
+dart -c pkg/testing/bin/testing.dart --config=pkg/fasta/testing.json
+```
+
+## Running dart2js
+
+```bash
+dart pkg/fasta/bin/compile.dart pkg/compiler/lib/src/dart2js.dart
+$DART_AOT_VM pkg/compiler/lib/src/dart2js.dart.dill pkg/fasta/test/test/hello.dart
+```