Fixes drawImage for thumbs
Limit the size of canvases to 5MP (iOS restriction)
Cache pages at the start of drawing, not the end.
Fix mishandling of incomplete, inverted masks.
Merge pull request #4932 from nnethercote/cache-pages-earlier

Cache pages at the start of drawing, not the end.
Merge pull request #4924 from yurydelendik/fixthumb

Fixes drawImage for thumbs
Merge pull request #4933 from nnethercote/fix-4926-masking

Fix mishandling of incomplete, inverted masks.
Merge pull request #4834 from dferer/canvas-max-size

Limit the size of canvases to 5MP (iOS restriction)
Halve the size of the PageView cache.
Fix PageView cache re-insertions.
Merge pull request #4937 from nnethercote/smaller-cache

Halve the size of the PageView cache.
Merge pull request #4936 from nnethercote/fix-cache-splice

Fix PageView cache re-insertions.
Added support for decrypting PDF 1.7/2.0 Algorithm 5 revision 5 and 6.
*Added AES128 Encryption
*Added AES258 Encryption/Decryption
*Added SHA256
*Added SHA512
*Added class to handle 8 byte integers and associated bit operations
*Added SHA384
*Added routines to handle new algorithm and perform PDF2.0 hashing.
SHA512 optimizations
Merge pull request #4938 from yurydelendik/2647AES256

Added support for decrypting PDF 1.7/2.0 Algorithm 5 revision 5 and 6. (perf)
Fix #3591 / list unsupported options
Adds test case for JPX COC marker
Refactoring error reporting in JPX
Merge pull request #4939 from yurydelendik/issue3591

Fixes JPX COC support / JPX error reporting refactoring
Prevent rendering unnecessary pages when the HOME/END keys are pressed

Currently (at least in Firefox) when the HOME/END keys are pressed, this will trigger unnecessary rendering of pages that lay between the current page and the first/last page. Avoid this by going straight to the first/last page instead.