bump crengine: add support for MathML (#7465)

Includes (among others):
- LVImg: Tweak JPEG decoding some more
- toStringV2(): fix (again) when target node is a boxing node
- LVFontCache::find(): give more weight to first fonts in list
- Page splitting: more accurate rendering progress
- getRenderedWidths(): fix nowrap around image/inlineBoxes
- Tables rendering: tweak column widths algorithm
- CSS: parse/handle "currentcolor", default for border-color
- CSS: add units 'ch' (just like 'ex')
- SVG images: proper alpha blending
- MathML: add parsing and rendering support files
- MathML: plug MathML code into crengine core
- MathML: <epub:switch/case/default>: accept MathML
- (Upstream) Make crengine.font.fallback.faces plural
- (Upstream) Option to not limit font size to a set
- Text: dont adjust space after consecutive initial marks/dashes
- Update German hyphenation patterns

base

@@ -1 +1 @@
-Subproject commit 3a754c72885c6538cb0418071b4546dbafee8724
+Subproject commit bfbc8a3e5c40a2d85653de1e4b93dc64cc8aea2a

frontend/document/credocument.lua

@@ -934,7 +934,7 @@ function CreDocument:setupFallbackFontFaces()
     -- names than ',' or ';', without the need to have to use quotes.
     local s_fallbacks = table.concat(fallbacks, "|")
     logger.dbg("CreDocument: set fallback font faces:", s_fallbacks)
-    self._document:setStringProperty("crengine.font.fallback.face", s_fallbacks)
+    self._document:setStringProperty("crengine.font.fallback.faces", s_fallbacks)
 end
 
 -- To use the new crengine language typography facilities (hyphenation, line breaking,