Merge pull request #676 from chrox/master

update k2pdfopt to version 1.6.3
Allow user to specify header font
1. Add Shift-H command to select page header font for crengine
2. Remove "(requires re-open)" from the Help of V command as it no
longer requires re-opening the file.
3. Replace the message "Redrawing" with "Formatting" as it describes
more accurately what is happening.
Merge pull request #677 from tigran123/creheadfont

Allow user to specify page header font for crengine
Modify those functions about the view_mode equal "page" when the kindle
in Horizontal screen state.
Merge pull request #692 from ZenRoi/master

Modify those functions about the view_mode equal "page" when the kindle in Horizontal screen state.
fix typo in crereader
fix gotoPercent in crereader
Merge pull request #702 from houqp/master

fix gotoPercent in page mode
use last_xpointer to keep reading progress for crereader
save last_percent in crereader for fileinfo
reset self.toc on document reformat
cre: load document afer set font
Merge pull request #704 from houqp/master

two bug fixes
Merge pull request #706 from houqp/master-fix

cre: load document afer set font
restore line space from config
bug fix: handle page mode in redrawCurrentPage
Merge pull request #713 from houqp/master

two bug fixes
fix bug in TOC construction in cre.cpp

first toc entry should start with index 1 instead of 0
Merge pull request #716 from houqp/master

bug fix for crereader's toc
bug fix: read css file name instread of content in cre:setStyleSheet