Reduce use of directory artifacts

Ensure node modules are installed in same action as they are used

Previously dependencies were installed by a separate action that ran
before the dependant action resulting in Bazel symlinking files in. This
can cause issues with some node tools.

Also added support for postinstall script on yarn_repository which
allows for arbitrary script execution for example to apply patches to
modules.

1.0 release

Major rework of rules to use native Bazel packaging and dependency
management.

Updates to support Bazel 0.6

Sandbox npm_repository install

Remove debug output

Ensure correct node prefix is used for install

Add option to skip npm_library export of individual yarn repo modules

Version update

Fix issues with symbolic links in node