Fix bug 375557 "No indication of cppcheck being run in background"
After clicking Analyze -> Cppcheck (Current Project), the Cppcheck tool view opens, but it's empty and does not say that analysis is in progress which is very misleading.
The fix adds notification messages to Problems View:
- At the start of analysis: "Analysis started..." This message will be removed with first problem report.
- At the end of analysis (if we doesn't have any problems): "Analysis completed, no problems detected."
For both messages we set current analysis path as problem location.
Test Plan: Tested with master branch
Reviewers: KDevelop, mwolff, kfunk
Reviewed By: KDevelop, mwolff, kfunk
Subscribers: mwolff, kfunk, kdevelop-devel
Differential Revision: https://phabricator.kde.org/D4816