GitLab

Moved the lua variable inspector tree widget into a separate dock on the right hand side in MainWindow.

refs #643

* Split up campvis-application executable into campvis-application library and campvis executable. This allows to create a Lua module for the stuff in campvis-application.
* Added Lua binding stub for campvis-application
* Revised LuaTable and it's offsprings to (almost) fully model the Lua table model
* Added MetatableLuaTable to model Lua's metatables
* LuaTable supports caching the current field state in a value map supporting lazy instantiation
* Added LuaTableTreeModel transforming the LuaTable structure into a QAbstractItemModel
* Extended ScriptingWidget to contain both a LuaTableTreeWidget containing a variable view as well as with a LuaCompleter automatically completing the typed Lua commands with the variables extracted from the lua state.

refs #643

refs #386

* Introduced two new tgt::LogManager log levels LuaInfo and LuaError.
* ScriptingWidget registers itself as logger and prints the Lua output into the console window.

* Implemented one single gloabel Lua VM for the entire CampVisApplication instead of one VM for each pipeline.
* The global Lua VM has a "pipelines" table/array, holding the pointers to each loaded pipeline
* ScriptingWidget support cycling through last executed commands via the arrow keys
* LuaVmState supports redirecting Lua's print() function to a custom one that uses tgt::Logmanager for printing (just as proof-of-concept). This shall later be extended to pass all Lua output to the scripting console.

With scripting enabled, the main window now has an additional scripting widget that allows to interact with a Lua VM. The current proof-of-concept implementation creates a Lua VM for every instantiated CAMPVis pipeline while the console just interacts with the first pipeline's one.
However, the Lua VM concept has to be reiterated later anyway. It may make more sense to have just a single central Lua VM for the entire application, which is shared by each pipeline.