Parallel analysis by default for C and C++ projects

Hello dear C and C++ users.

We are very pleased to announce that C and C++ projects are now going to be analyzed in parallel by default, using all available CPU cores.

Additionally, we polished many things by fixing bugs, bringing specific improvements and silencing a few false positives.
The exhaustive list is available in the release notes.

All this is already available on and will be available with SonarQube 9.5 starting from Developer Edition.