Merge pull request #82 from esbullington/es6_math

Added type signatures for ES6 additions to Math object
Start a node stdlib interface file
Declare optional parameters according to HTML standard

According to
https://html.spec.whatwg.org/multipage/webappapis.html#timers timeout
and handles of setTimeout and friends are optional.
Merge pull request #94 from jeffmo/node_interface_files

Start a node stdlib interface file
Merge pull request #98 from lbolla/setTimeout

Declare optional parameters according to HTML standard
type and endings in options are optional arguments

According to https://developer.mozilla.org/en-US/docs/Web/API/Blob.Blob type and endings are optional arguments.
(http://dev.w3.org/2006/webapi/FileAPI/#dfn-BlobPropertyBag also says type is optional, but has no endings argument at all)
Merge pull request #113 from tcoopman/patch-2

type and endings in options are optional arguments for Blob constructor
Add type signature for node `Buffer`
Add type signature for node `dgram` module
Add type signature for node `dns` and `dgram` modules
Add type signature for node `domain` module
Add type signature for node `events` module