fix: base64 encoded image download filename

[drewmperkins]

I was using base64 encoded image strings, and when trying to download the picture, the parsing currently in place does not work.

ex: self hosted - http://example.com/file1.png
filename = file1.png
ex: base64 encoded - data:image/jpg;base64,/9j/....
filename = some characters at the end of the last forward slash.

I propose adding an additional argument to the IAlbum interface called fileName, to allow users to override the default attempt of naming downloaded files.

[themyth92]

hi @drewmperkins , can u help to resolve conflict and retest again see if it works for u or not. tks