Build libcurl as part of the 'make third' rule...

...without adding it to the standard list of required third party
dependencies.
Load the usecmap directives recursively for builtin CMaps.

Fixes bug introduced in commit 1679c1e7a89ae62260fd84ce55c6bef376c6e6ba:

    Optimize UniXXX CMap files.
Fix 695247: Use exponential realloc pattern and qsort for huge paths.

Grow the edge list using an exponential realloc pattern.
Use qsort for huge paths and only fall back to the simple
shell sort for small paths.
Fix 695222: Treat non-breaking space (U+00A0) as white space for search.
Fix windows VS builds.

Fix broken solution file and add project entries for new files.
Flush pending text on a change of CTM.

Without this, comparefiles/Bug695086 renders the barcode test upside
down.
Bug 695183: Inflate large buffers at a time for speed.

When I changed the stream implementations to use implementation
specific buffers, rather than a generic public one in every fz_stream,
I changed fz_read_byte to only get a single byte at a time.

I noted at the time that the underlying stream was free to decode
larger blocks if it wanted too, but I forgot to actually do this for
the flate decoder. Fixing this here should solve the speed issues.
Add ftdebug.c to thirdparty freetype build.

Allows compilation with -DFT_DEBUG_LEVEL_TRACE to track down buggy fonts.
Fix 695041: add special fast case for 8bpp TIFF predictor.
Fix 695261: separate TM and CTM in outline extraction and stroking steps.

We used to extract the outline using the combined TM*CTM matrix and
use the identity transform for stroking, thus ending up with the wrong
line width.

If we instead extract using the TM and then stroke with the CTM we get
the correct results.
Bug 695260: Fix error handling in do_xobject

Various functions (such as fz_begin_group) handle errors internally
by use of the error_depth parameter. This means that if we call
them, we MUST ensure that we call the appropriate closing function.
Similarly, if we don't call them, we should NOT call the closing
function.

In order to ensure we do this correctly, we introduce a cleanup_state
variable that says which ones we tried to call.

This cures the original bug.
Fix 694579: Implement "zoom to fit page".

Add a new function pdfapp_autozoom to fit the page to the window by comparing
the aspect ratios of the page and the window to choose whether to fit
horizontally or vertically.
Set a faster default transition.
Fix 694518: Implement continuous scrolling with keyboard.
Fix 693494: Support media buttons for navigation on X11.
Fix 693517: Support /SMask/Matte preblended images.
Save a bookmark before jumping when using the 'g' command.