Fix links on RacketCon web page.

Pointed out by J_Arcane on IRC.
Remove out of date OC docs and replace with pointer to the OC package.
improve GC handling of out-of-memory

There's a point in attempting to allocate a new large page
where it makes sense to GC and try again.
Mac OS X: incorporate Pango repair for Yosemite

Pango 1.36.6 fixes the problem, so update native libraries
and the Coretext patch.
racket/gui gtk: workaround problem with async IBus input method

Affects Ubuntu 13.10 and 14.04, especially with multiple processors.
ffi/unsafe/objc: fix `objc-is-a?` to recognize subclass instances

This repair turns out to matter for Mac OS X 10.10, where creating
a list box in a frame somehow makes the frame an instance of a
subclass (that implements notifications of some sort, I think).
That subclassing broke an `(objc-is-a? ... RacketWindow)` test to
recognize windows that belong to a particular eventspace.
Added fllog2near
Added fast-flfsa/error and flfsa/error (fused square-and-add)
Altered `keymap%` to not claim to handle key events that it doesn't

Previously, `keymap%` would return #t for all shift, ctrl, and key release
events. DrRacket's editors would then not handle those events (correctly,
as they shouldn't handle already-handled events), meaning that the events
weren't sent to any snips.
racket/gui cocoa: adjust control font for 10.10
Add `get-all-pkg-scopes`.
racket/gui win32: fix Space handling of buttons and checkboxes

Suppress WM_KEYDOWN messages to a button or checkbox, so that the
top-level window takes care of Space and Return for a button or
checkbox with the keyboard focus.

Closes PR 14710
racket/gui keymap: adjust handling of 'control, etc., events

If a keymap has a grab, then discard key events that are modifier
changes or key releases.

Adjusts commit 8ba8d01ec0 so that Ctl-u work in DrRackt (and
other framework-based programs).
fix dot layout when children are deleted

closes PR 14718
fix cross-module function inlining and argument use-count tracking

Order mismatch between tracking an use could cause a multiply-used
argument to be treated after inlining as a single-use argument.

Closes PR 14717
make installers: avoid dot-files (like ".gitignore") in installers

Closes PR 14716
distro-build/readme: adjust content of generated README files

Relevant to PR 14714

(I think the remaining suggestions in the PR are about the build
configuration.)
Windows installer: uninstall "collects"

Closes PR 14715, where Eli describes the repair

(Probably, the "collects" directory was missing from the uninstaller
list because "collects" moved under "lib" in an intermediate variant
of the directory organization.)
moved a manual test over
interpolation for recorded animation; for David for now