Merge pull request Ericsson#3791 from bruntib/fix_fixit_test

[test] Fix fixit test

[version] Bump up to version 6.21.0-rc1

Merge pull request Ericsson#3742 from vodorok/docs

[doc] Extend Cppcheck documentation

[version] Bump up to version 6.21.0-rc1

[bugfix] Determine stats capability in pre-analysis

get_analyzer_checkers() should be used for querying checker list because
this can be used for getting modeling checkers too. Pre-analysis depends
on the existence of some modeling checkers.

Merge pull request Ericsson#3620 from csordasmarton/new_features_6.19.0

[gui] Describe new features in 6.19.0

[version] Bump up version to 6.18.2

[gui] Fix number of outstanding reports chart

Let's assume that a bug was detected yesterday at 3PM and I want to view
this chart today at 1PM. In day resolution we used the current date as a
starting point and based on the interval length (e.g.: 7 days) we subtract
x days from the current date. For this reason the grap will not show me this
bug which was detected yesteday, but it assumes that is was detected today.

With this patch we will set the starting date to the end of the current date
which will solve this issue.

Merge pull request Ericsson#3494 from dkrupp/remove_virt_destr_checker

Removing cppcoreguidelines-virtual-class-destructor from the profiles

Merge pull request Ericsson#3432 from bruntib/add_labels_to_checkers

[config] Add some labels to checkers