bump crengine, show progress meter on load/re-rendering (#5406)

Includes:
- Adds tinyNodeCollection::getStatistics()
- epubfmt.cpp: cleanup indentation and small optimisation
- Add more progress callback events
- Optimisation: avoid re-init for EPUBs with embedded fonts
- Fix: don't draw border when border-color: transparent
- CSS: ignore 'inherit' inside font-family

Show a small progress meter at top left of screen when
crengine is loading, re-rendering, and saving cache file
(after a 2 second delay to not be bothered on small books).

Also add a wrapper for the last remaining bit of code that
was accessing _document directly (:getPageOffsetX()).

frontend/document/credocument.lua

@@ -435,6 +435,10 @@ function CreDocument:getPageFromXPointer(xp)
     return self._document:getPageFromXPointer(xp)
 end
 
+function CreDocument:getPageOffsetX(page)
+    return self._document:getPageOffsetX(page)
+end
+
 function CreDocument:getScreenPositionFromXPointer(xp)
     -- We do not ensure xp is in the current page: we may return
     -- a negative screen_y, which could be useful in some contexts
@@ -806,6 +810,10 @@ function CreDocument:enableInternalHistory(toggle)
     self._document:setIntProperty("crengine.highlight.bookmarks", toggle and 2 or 0)
 end
 
+function CreDocument:setCallback(func)
+    return self._document:setCallback(func)
+end
+
 function CreDocument:isBuiltDomStale()
     return self._document:isBuiltDomStale()
 end
@@ -822,6 +830,10 @@ function CreDocument:getCacheFilePath()
     return self._document:getCacheFilePath()
 end
 
+function CreDocument:getStatistics()
+    return self._document:getStatistics()
+end
+
 function CreDocument:canHaveAlternativeToc()
     return true
 end