bluetooth: Fix replying to getDefaultAdapter() before it is ready

Before we can reply to that message we need to be sure that we have
all the information about the adapter (its path, address, for example)
or that information can't be obtained (BlueZ isn't running).
bluetooth: Cancel all pending calls on the destructor

We explicitly leak the GCancellable, because the calls are cancelled
asynchronously and they may survive BluetoothContext. We will only
free them on the shutdown callback of the extension.
bluetooth: Add handler for RFCOMMListen message

This will allow for ServiceHandlers, the server side of RFCOMM, to be
created.
bluetooth: Add support for registerRFCOMMServiceByUUID

This will create a service handler (in BlueZ terms, a socket listening on
an RFCOMM channel and a SDP record identifying this service), which has a
callback that will be called when a remote device connects to this service.
bluetooth: Add support for notifying that a socket as data available

This adds the SocketHasData message that has as parameters the data
that came from the socket and the socket file descriptor number on
which it came.
packaging: Link with libbluetooth

Now that we are using functions provided by libbluetooth we need to
link against it.
bluetooth: Add a simple workaround for setPowered()

When the adapter is already powered we may just call the callback.

This is just a temporary solution until there is a proper solution for
the problem of the adapter exiting the USB bus, when it is powered down.
Merge pull request #152 from vcgomes/bluetooth-set-powered-workaround

bluetooth: Add a simple workaround for setPowered()
Merge pull request #153 from vcgomes/bluetooth-fixes

[Bluetooth] Fixes dealing with sync replies and the instance destruction
Merge pull request #154 from vcgomes/bluetooth-service-handler

[Bluetooth] Add registerRFCOMMServiceByUUID
Add a JavaScript Lint script that uses Google's Closure Lint.

It will simply run Google's closure Lint, but ignoring
the absence of JSDocs and extending max_line_length to 100 columns.
[Notification] Missing passing argument to NotificationCenter.get()
[Notification] Fixes default values of attributes
[Bluetooth] Fix bluetooth_api.js according to our style
[Notification] Make removal immediate, add NOT_FOUND_ERR
[Notification] Throw when calling constructors without new
Add a README file.
[Notification] More default values for properties
Merge pull request #157 from cmarcelo/notification-js-api-fixes

Notification js api fixes
[Time] equalsTo, lessThan and greaterThan are now throwing exceptions