Fixed new passage positioning + other fixes

* Fixed the glitchy positioning of new passages - they are now placed
closer to the intended location.
* Passages tagged with 'Twine.' tags are now colour-coded gray.
* Altered the Greeking of zoomed-out passages to reflect the actual
passage text length.
* Doing a find-replace where the 'replace' string contains -, /, [, \, ]
or ^ no longer adds needless backslashes.
* Added syntax highlighting for raw inline HTML tags.
* Removed the 'Report a Bug' menu item.
* Incremented the version number.
* Updated the 'About' box credits.