TODO:

- [x] Fix c.fill issue
- [x] Create Element structure with pads and connections
- [x] Get a list of GStreamer elements in dialog add plugin
- [x] Add plugin details in the element dialog
- [x] Draw element with its pad
- [x] Be able to move the element on Screen
- [x] Create connection between element
- [] Control the connection between element
  - [x] unable to connect in and in out and out
  - [] unable to connnec element with incompatible caps.
  - [x] unable to connect a port which is already connected
- [] create contextual menu on pad or element
- [] upclass the element
- [] create a crate for graphview/node/port
- [x] save/load pipeline
- [] Run a pipeline with GStreamer
- [] Run the pipeline with GStreamer
- [] Control the pipeline with GStreamer
- [x] Define the license
- [] Connect the logs to the window
- [] Create a window for the video output
- [] Add multiple graphviews with tabs.

## Code cleanup

[] remove useless code from graphview