PCF

Access to internal properties in traits causes `property.internal`

2

### Bug report I have a trait with a private property. To prevent it from being accessed directly, I have marked it as internal so that a getter method is...

New arguments

2

This PR includes also #603. I have added a number of arguments that I use in my project via extensions. The namespaces are structured according to the ffmpeg documentation, because...

Change private WithArgument methods to public

1

FFMpegArgumentOptions.WithArgument is already public, which allows extensions. However, this is not nice semantically, as the global arguments (e.g. `-hide_banner`, `-nostats`) have to be given as input arguments. So I changed...