Which static code checker do we want in the CI? (was ACTS-455)

Original author Robert Johannes Langenberg @rlangenb

Paul added several static analyzers to the CI in this branch and converted some of the output to html with code and results from the checker side by side.

We should decide which of these analyzers we want to keep, and once we decided which options we want to keep. <~asalzbur> could you comment regarding scan-build, since you seemed to have it working locally inside your Xcode?

Since they run quite long we could run them manually on the CI, but this may also be a good time to decide if we want static analyzers as build target as suggested by Moritz: https://its.cern.ch/jira/browse/ACTS-376