ui: Improved user experience of error display

* label errors as errors instead of references in file snippet headers
* show number of fatal errors in file snippet headers as well
* only show the first 10 error snippets open, remaining collapsed
* don't show status message after parsing in red on errors
* don't show stats of parsing when project was only loaded

src/lib/CMakeLists.txt

@@ -155,6 +155,7 @@ add_files(
 	data/DefinitionType.cpp
 	data/DefinitionType.h
 	data/ErrorCountInfo.h
+	data/ErrorInfo.h
 	data/HierarchyCache.cpp
 	data/HierarchyCache.h
 	data/IntermediateStorage.cpp