Add getWorkerTask functions

They provide a way to easily create a task in a worker thread and get a handle to it.

Signed-off-by: Luca Niccoli <lultimouomo@gmail.com>
fix #609 - sendMail doesn't work for SSL/TLS smtp connections

- need to establish an SSL connection right away
Update json.d

Add opDollar to the Json struct for convenience slicing Json arrays.
Merge pull request #616 from ncoe/master

Add opDollar for convienience slicing arrays
Default to safe SSL/TLS cipher suites and disable TLS compression.

Note: still missing a way to set up the DH parameters.
Merge pull request #609 from MartinNowak/fix609

sendMail doesn't work for SSL/TLS smtp connections
Merge pull request #601 from lultimouomo/getWorkerTask

Add getWorkerTask functions
Remove deprecated symbols and deprecate symbols that have been scheduled for deprecation.