Add `-report` and `-psnr` options

Parameters I currently use via additional params are:
vbv-maxrate=5000:vbv-bufsize=30000

(this constrains the stream rate on average to around 5mbps while allowing some bursting as needed up to a ~6 second buffer. For any streaming use case this produces a far more deliverable file than pure crf)

Parameters I currently use via custom options are:
-psnr -report

this produces some data on the result quality

I think both of these are worth recommending for many use cases. I also would like to see some of the highlights of --report surfaced after job completion in the UI. Note that all of the above are currently supported via additional/custom so I wouldn't bother implementing if the feature wasn't likely to be merged.

The other enhancement areas I would like to see are some parameters I don't think can currently be controlled by the config profiles (please let me know if these are already supported):
* max width (4k->1080)
* audio conversion codec
* audio bitrate
* audio select first 6 channel in preferred language instead of the 7.1

For all of the above, if the features make sense and would be welcome I am happy to either treat this as a feature request or implement and send a pull request. UI design isn't necessarily my strong area. Let me know, and Thanks!