Bugfix for numbering with ol sublists
Merge pull request #3 from chphmh/bugfix-ol-bookmark-bookdark

Bugfix for numbering with ol sublists in themes BookMark & BookDark
v1.3.5: UI improvements

* Sub-navigations now open vertically to utilize all the available
space.
* Added an optional subject field to the "Send by email" dialog.
* The file name is now pulled from the first H1, if available.
Merge branch 'pr/3'