Clean up whitespace errors.
Some Makefile cleanups.
Add begin_page and end_page calls to device interface.
Support begin/end page calls in text extraction device.
Fix tiling breakage from b975f1b

It seems that the code for begin_tile currently assumes that area
is passed in untransformed. Maybe this is something we should
look at, but for now commit it to revert the rendering problems.
Call begin/end page in pdfapp.
Bug 694303: Fix various problems in pdf parsing

Spot a 'startxref' of 0 as being an error; otherwise the code
falls through and we SEGV.

Also update the pdf_repair_obj function to cope better with the new
way we parse ints. Previously we parsed ints into the buffer and
atoi'd them there - to step backwards over the int was therefore a
matter of stepping backwards over the specified number of chars.

In the 'new' code (now quite old) we parse ints directly, hence we
cannot do this stepping back. Also, stepping backwards by more than
1 byte is risky anyway. We therefore adopt a smarter approach of
returning the next lexed token from pdf_repair_obj.

Thanks to zeniko for reporting these problems and providing a test
file.
Remove stray code from last commit.

When creating the previous commit, I considered an alternative way
of working. While we didn't use this in the end, I forgot to remove
it from the code before committing. Stripping it out here. Sorry.
Bug 694315: Fix locking problem in error case.

In some cases, the existing code can leave the GLYPHCACHE lock held
if an error occurs during type3 rendering. Correct this oversight.

Thanks to zeniko for spotting the bug and providing a fix.
Make display lists reference counted objects.

Remove fz_free_display_list from the API; instead use fz_drop_display_list.
Fix typos in comments.

Spotted by Vincent Torri. Many thanks!
Bug 694313: Fix potential double frees of objects

Thanks to zeniko for spotting these.
Addition of display list rendering in WinRT library

The display list rendering is used when scaling within the current page to
enable quicker response.
Addition of zoom in and zoom out control on top app bar.

Also rework of some UI interactions to avoid zooming, text search, etc when
in a specialized view like contents or reflow (webview)
Addition of locking cache for display list in winRT library
Fix error handling in WinRT code (that I broke).

Just before pushing the previous commit of Michaels, I removed
an fz_var, thinking it wasn't required. After discussing it with
him I realise that it was needed, so reintroduce it here with
another error handling tweak. Apologies!
Missing update for slider when page is already rendered.