Update demo.py

[SivanSchwartz]

[alexcwsmith]

The issue with this is that right now the init_new_project function does not only take paths to individual video files to add to project, but the 'videos' parameter can also be a list of folders, each containing videos to add. The way the code is now addresses that easily, using glob as in this PR would not. You could use glob in a for loop to assemble the list of videos from multiple folders, but the current solution is simpler.