[poppler] Work-in-progress for Optional Content (aka layers)

[Brad Hards]

I've been slowing working on the Optional Content support (PDF spec 4.10 for 
the morbidly curious) for poppler (based on bug 12661).

The attached patches show where I'm going in terms of GUI support. Feedback 
appreciated. Patch 2 can be ignored.

The next stage is to actually make the rendering process take notice of the 
OptionalContentGroup settings.

After that, I need to fold in Optional Content Member Dictionaries, and then 
Visibility Expressions (maybe).

Brad
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-Start-of-Optional-Content-Group.patch
Type: text/x-diff
Size: 1751 bytes
Desc: not available
Url : http://lists.freedesktop.org/archives/poppler/attachments/20071123/1d0a6671/attachment-0003.patch 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0002-Suppress-editor-backup-files.patch
Type: text/x-diff
Size: 486 bytes
Desc: not available
Url : http://lists.freedesktop.org/archives/poppler/attachments/20071123/1d0a6671/attachment-0004.patch 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0003-Big-update-for-the-Optional-Content-work.patch
Type: text/x-diff
Size: 33439 bytes
Desc: not available
Url : http://lists.freedesktop.org/archives/poppler/attachments/20071123/1d0a6671/attachment-0005.patch