support kate's LSP plugin
This requires a MR in kate to actually enable the plugin (and add some API we need) still.
This MR
- fixes support for kate's toolviews
- adds support for config pages from kate's plugins
- sets an option on the LSP plugin to disable the c, cpp, php, python and (?) qmljs languages because we support them ourselves.
It works surprisingly well with surprisingly little effort. Of course not everything is ideal, e.g. we now get kate's diagnostics view for LSP and KDevelop's diagnostics view for the duchain languages, but it's a start.
Edited by Sven Brauch