New players and tutorial

New applications were added to the players list recently: - HISE - sfizz - liquidsfz

and a new tutorial from Sonoj 2019 Convention on how to recording samples using Ardour and LinuxSampler by Christoph Kuhr to our Video tutorials section.

Thanks to Stefan Westerfeld for our first GitHub pull request! And to Sonoj organization for the video tutorial contribuition.

Last but not least, for those like me who prefer IRC we have now also an IRC channel on freenode server.

/join us!