bump crengine: support min/max-width/height, 2-pages tweaks
bump crengine: support min/max-width/height, 2-pages tweaks

Includes:
- EPUB ncx TOC: allow items with an empty title
- resizeImage(): restore original scaling options code
- CSS: parse and store min/max-width/height
- Add getStyledImageSize() ensuring min/max-width/height
- renderBlockElementEnhanced(): ensure min/max-width/height
- 2-pages mode: add option twoVisiblePagesAsOnePageNumber
- TOC, PageMap: save the visible pages number they were build for
- 2-pages mode: tweak header drawing
- Header: add option to display time as 12-hours clock
- 2-pages mode: decrease min middle margin from 1.2 to 0.8em
- Add LVDocView::getDocumentRenderingHash()
- (Upstream) Text: don't remove trailing space on last word if pre
- (Upstream) Font: replace notfound glyphs only on last fallback font
- (Upstream) Add a few lString8 methods

koreader/koreader,koreader/koreader,poire-z/koreader,poire-z/koreader,Frenzie/koreader,pazos/koreader,NiLuJe/koreader,NiLuJe/koreader,Hzj-jie/koreader,mwoz123/koreader,Frenzie/koreader