Readme: update install instructions
Update Postgres.app to v9.3.4.2

  from version 9.3.4.1
Update node-webkit to 0.10.0

`link` stanza has been removed as it does not serve normal usage of
node-webkit.

node-webkit is a runtime targeted by application developers.
Usage of node-webkit usually takes one of two forms:
- launching the binary with development code as argument, either by
  CLI or drag-and-drop.
- bundling a copy of the binary with release code, for packaging and
  distribution.

Neither usage is aided by a symlink; a known binary location, which
Cask provides, is sufficient.

Addendum: `version` value is reused in `url` stanza to facilitate
future updates.
Merge pull request #5470 from ndr-qef/node-webkit

Update node-webkit to 0.10.0 and remove `link` stanza
Merge pull request #5472 from vinkla/fix-5471

Update Postgres.app to v9.3.4.2
graphviz 2.36.0: New formula
Merge pull request #5474 from vitorgalvao/fix-5473

graphviz 2.36.0: New formula
Merge pull request #5441 from rstacruz/patch-1

Readme: update install instructions
Merge remote-tracking branch 'upstream/master'

Conflicts:
	Casks/postgres.rb