[[ Emacs ]] Add top-level .dir-locals.el file.

Add project-specific settings file with basic indentation rules that
make Emacs format source code a little more like XCode does.
Remove iOS from prebuilt fetch script

There are some issues fetching/extracting the iOS prebuilts; disabling them for now until it can be resolved.
Merge pull request #1293 from peter-b/misc-emacs

[[ Emacs ]] Add top-level .dir-locals.el file.
Fixes to a broken docs file
Merge branch 'refactor' of https://github.com/runrev/livecode into refactor
[[ feature-sendonidle ]] Add "send ... when idle" syntax.
[[ feature-sendonidle ]] Queue idle priority messages with +Inf dispatch timer.
[[ feature-sendonidle ]] Don't allow duplicate idle priority messages.

If an idle message is scheduled, search for matching messages already
in the queue.  If one already exists, update parameters of the message
that's already queued and return its ID.
[[ feature-sendonidle ]] Dispatch idle priority messages iff nothing else to do.

Adds a parameter to MCUIDC::handlepending() to enable dispatch of idle
messages.