Supporting Flexbar in easybuild

[cmeesters]

Hi,

this issue is related to #38. I just managed to install flexbar upon user request on our cluster using tbb 2020.3 and seqan 2.4.0.

However, there are so many deprecation warnings, that supporting flexbar for the easybuild community does not seem appropriate any longer.

It seems development has ceased? Or are there any plans supporting the software with regard to seqan 3?

Cheers Christian