Add support for picasa ini files for metadata

[lancerushing]

No description provided.

[lancerushing]

Need to figure this out.

[lancerushing]

There are a few things I want to add, but I wanted to get your input before I add too much polish.

1. Which pattern to use to inject the app.Picasa flag into localasset? Are you good with me add picasa bool to the signature of ExploreLocalFolder(ctx context.Context, fsyss []fs.FS) New: ExploreLocalFolder(ctx context.Context, fsyss []fs.FS, picasa bool)

2. I'll add more tests (especially upload_test.go)

3. I used github.com/spf13/afero to help with os.file abstraction. I noticed that we have github.com/psanford/memfs. I think afero is nicer, more active, etc. But it does have many more dependencies... 🤔

Do you want me to:
a) leave both in (doesn't mater)
b) convert the memfs code to afero
c) convert the afero code to memfs

Let me know, and I will get the code done.
-Lance