Merge pull request #739 from chrox/new_ui_code

bugfix: restore original zoom mode after cropping
Merge pull request #741 from chrox/new_ui_code

bugfix: calculate current config value or arg at runtime
bug fix: reader crashes when table of content is empty
fix visible_area recalculate for manual crop in reflow mode
Merge pull request #742 from houqp/new_ui_houqp

bug fix: reader crashes when table of content is empty
always make sure we switch to page mode in manual cropping
Merge branch 'new_ui_fix' of git://github.com/houqp/kindlepdfviewer into new_ui_code
fix visible_area recalculate for manual crop in reflow mode