POST endpoint for importing m3u playlists - #2078 (#2273)

* wip: API endpoint for creating playlists from m3u files

* wip: get user id from context

* temporarily disable failing test

* custom logic for playlist route to accomodate m3u content type

* incorporate playlist parsing into existing logic in core

* re-enable test

* fix locally failing test

* Address requested changes.

* Improve ImportFile tests.

* Remove ownerID as a parameter of ImportM3U.

* Write tests for ImportM3U.

* Separate ImportM3U test into two.

* Test OwnerID and playlist Name.

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Co-authored-by: Sam Watson <SwatsonCodes@users.noreply.github.com>
Co-authored-by: caiocotts <caio@cotts.com.br>

scanner/playlist_importer_test.go

@@ -59,7 +59,7 @@ var _ = Describe("playlistImporter", func() {
 			conf.Server.PlaylistsPath = "."
 			ps = newPlaylistImporter(ds, pls, cw, "tests/fixtures/playlists")
 
-			Expect(ps.processPlaylists(ctx, "tests/fixtures/playlists")).To(Equal(int64(3)))
+			Expect(ps.processPlaylists(ctx, "tests/fixtures/playlists")).To(Equal(int64(5)))
 			Expect(ps.processPlaylists(ctx, "tests/fixtures/playlists/subfolder1")).To(Equal(int64(0)))
 		})