Add gif support for exercise photos.

[BeatLink]

Describe the feature you'd like
Hello, I was wondering if gif support could be added to exercise photos. That way, gifs showing the exercise form could be added by users.

Describe alternatives you've considered
None so far

Additional context
Nothing Here

PS: Great work on Fast N Fitness by the way. Best open source workout app I've found.

Thank you.

[BeatLink]

@islam2hamy is also requesting support for .mp4 along with gif for exercise photos