Please, allow use of x264 profiles for encoding

Hi.

To record video without making a lot of demand of CPU computation (especially for computers that are older, but not only for such computers), it would be very good if, when generating a video encoded with x264, guvcview allowed the use of x264 profiles.

If very computationally expensive options are used for x264, then, at least with laptops, one very nasty side-effect is that the fan of the computer gets very loud and can interfere with the audio recording (sometimes, to the point of covering the voice of the recording).

To avoid that and in particular, the ultrafast preset of x264 (that generates Constrained Baseline Profiles) is (depending on the processor) generally able to record videos with reasonable sizes and modest use of CPU.

Please, do consider the use of these profiles (not only the ultrafast profile, but some others, like superfast, veryfast etc.).

This will make the program much more intutitive to use with respect to the UI, use tried and true defaults and, quite probably, economize billions of cycles of computers all around the globe.

Thanks in advance,

Rogério Theodoro de Brito.