[README] add Requirements section (coder#1000)

* [README] add Requirements section

This is based user feedback and testing. This may expand if need be

Signed-off-by: Ayane Satomi <chinodesuuu@gmail.com>

* [README] raised the bar a bit more

Apparently we were targeting GLIBC 2.17

Signed-off-by: Ayane Satomi <chinodesuuu@gmail.com>

Update nbin

The latest version contains a fix for passing null options when reading
a file. Fixes coder#544.

Fix extensions that try to load from node_modules.asar

Should allow manual installation of bracket pair colorizer 2: coder#544.

Add missing VS Code version to git tag

Fix "no authentication" message with custom password

Fixes coder#757.

Move OSX package task into build script

This is to match how the other binaries are built. Also made some
changes to make the Docker containers clean up for when you are running
this locally.

Show hidden files by default

Since there is no other way to enable hidden files, it seems better to
enable it by default otherwise there are some folders/files you simply
can never open from the dialog.

Set NODE_ENV and VERSION when building (coder#700)

* Set NODE_ENV and VERSION when building

Should fix the version flag not reporting correctly as well as enable
the service worker and prevent the 404 hmr requests again.

* Log env vars

To help make sure it's built correctly when looking at the Travis logs.

Don't try to create builtin extensions directory

Since this will be a path in the binary that we don't want to create on
the user's system. I also removed the option to override it; it doesn't
seem like a great idea since you'd always want those builtin extensions.
This way we also don't have to check if the option was passed and only
create it if that was the case.

Fix clipboard pasting