[Cin] Blur plugin: Alpha determines radius

[Andrea paz]

> can anyone try Cin-HV 5/6/7 (may be in VM?) and see how this plugin work there

I put Ubuntu 18 in VM to try the Blur plugin. I tried to install the
cinelerra-HV binary but it gives me error:

error  libpng12.so.0 not such file or directory.