Feature/1.32.0 update (#117)

* Update VS Code to 1.32.0

* Update patch

Most changes are moved files, most notably shell.contribution.ts which
is now main.contribution.ts.

Also:
- repl.ts no longer uses isMacintosh
- shell.ts doesn't exist
- added back the commented-out CSP headers

* Use es6 target for bootstrap-fork

* Directly reference cross-env binary

yarn and npm find the binary just fine when running the tasks from the
root but it doesn't work if you run one of those tasks directly from
within those directories.

* Update import paths and bootstrap-fork ignores

* Increase memory limit for building default extensions

* Fix invalid regex in Firefox

* Update startup function

* Fix global.require error

* Update zip extract arguments

* Update travis to minimum required Node version

* Always chmod executable dependencies

Fixes EACCESS errors for users that had the files unpacked before we
added the chmod call.

* Remove unused var declaration