Create playlist, video generator and video player (#489)

Co-authored-by: Ivan Malison <IvanMalison@gmail.com>
Reviewed-on: railbird/railbird-mobile#489
Reviewed-by: Ivan Malison <ivanmalison@gmail.com>

src/schema.gql

@@ -217,7 +217,6 @@ type VideoGQL {
   playlist: HLSPlaylistGQL
   tags: [VideoTag!]!
   homographyHistory: [HomographyInfoGQL!]!
-  currentProcessing: VideoProcessingGQL
 }
 
 type UploadStreamGQL {
@@ -225,7 +224,7 @@ type UploadStreamGQL {
   linksRequested: Int!
   uploadsCompleted: Int!
   segmentProcessingCursor: Int!
-  lastIntendedSegmentBound: Int
+  lastIntendedSegmentBound: Int!
   isCompleted: Boolean!
   lowestUnuploadedSegmentIndex: Int!
   uploadCompletionCursor: Int!
@@ -293,16 +292,6 @@ type IntPoint2D {
   y: Int!
 }
 
-type VideoProcessingGQL {
-  errors: [VideoProcessingErrorGQL!]!
-}
-
-type VideoProcessingErrorGQL {
-  message: String!
-  startSegmentIndex: Int
-  endSegmentIndex: Int
-}
-
 type PageInfoGQL {
   hasNextPage: Boolean!
   endCursor: String