* Providing a "refresh" function for triggering a refresh from inside the lib
Some other glitches were fixed too:
* LibraryManager wasn't thread-safe
* Library destructor wasn't unregistering
* Crash when re-registering the same library again
* In LibrariesTest normalization of layouts must not include
re-creation of library references to avoid side effects.
Save without context.
* Added missing files
* Fixed unit tests.
* First implementation.
* PORT BACK: fixed a few flaws (fixed-width side panel ..)
1. On "save as" the filename displayed in the cell view selection box
was not updated
2. The width of the library and cellview panel could not be reduced
below the width of the combo boxes in the headers. So the
panels might have become pretty wide without being able to reduce
them.
* Implemented #560 (multiple techs on libraries)