* Fixed issue-1131 (do not show files in MRU lists which do no longer exist)
The solution consists of an extension of the Action system allowing to
dynamically hide or disable items. This currently works for menu items only.
This feature is used to dynamically *disable* (as of now, not hiding)
items from the four MRU lists corresponding to non-existing files.
In addition, a "clear list" menu has been added to the MRU lists.
* Small enhancement: file names can be URIs
As a way to trigger actions inside the layout view
and plugins.
Right now, the layout view's menu is only a rudimentary one
as it lacks the top-level menus usually provided by the main window.
* Fixed first issue (UI problem with GDS2Text options)
* Fixed problem with 'save' when the file extension does not indicate one of the known formats
In this case, and when plain 'save' is used, the original format is delivered.
The session files also store the original format now.
The statistics page will now indicate the format of the file that was loaded.
* Some doc fixes as preparation for PDF generation
* Some doc bug fixes and enhancements for PDF manual generation
* Fixed a number of invalid references found during PDF generation
* Enable PCellDeclarationHelper doc for help system
* Fixed doc text
* Fixed some doc issues with invalid links etc.
* WIP: first attempt to fix issue-983
* WIP: bugfixes
* Fixed a problem with displaying empty cell dimensions, one warning
* Another fix: don't allow proxy cells to be selected in the instance properties dialog. This creates a confusing behaviour
* Fixed a few flaws in the cell selection scheme on the instance properties dialog.
* Early warning when trying to build a recursive hierarchy.
* Another fix: avoid too much undo in case of errors thrown during 'apply' followed by 'cancel'
* First attempt to fix issue 984
* Fixed issue-983 solution
* Fixed the modification status of PCell parameters for 'apply to all'