A simpler way to create a SOAAPy build.ninja.

To do the Capsicum SOAAP work, we need to regenerate Chrome's build.ninja file and then apply SOAAP changes to it. Rather than committing a particular build.ninja file to revision control (which will, among other things, hardcode a particular user's SOAAP path), let's commit a diff that can be used to patch Gyp-generated Ninja files.
Remove 'out' directory from revision control.

When we build with different options, we need to re-Gyp the Ninja files. Now that we have a /capsicum/soaap-ninja.patch, people should run './build/gyp_chromium --depth .' and then apply the patch to the build.ninja file.