Rewrite WelcomePage

[danirabbit]

• Inline namespace
• GObject style
• Make sure we create buttons before we try to change their visibility by adding signals at the end
• Reduce variable scope where possible
• Update replay button title and subtitle when last-stopped changes
• Update replay button visibility and launch the correct file when current-video changes
• DRY

[jeremypw]

See inline comment

[jeremypw]

It still seems to suffer the issue in #187. Are you not getting that issue? The problem seems to be that the "last-stopped" setting changes when the window is destroyed from "0" to "0.002..." for some reason. A quick fix would be to change the test in update_replay_title () from> 0 to > 0.003 or change the test in the destroy callback. Note that this issue only seems to occur with_short_ videos (e.g. 1 minute)

[danirabbit]

I'm not experiencing and issue with the time save being set to a non-zero value on destroy.

I think this sounds like a bug in a different part of the codebase though and I'm hesitant to add a workaround here instead of solving it at the source

[jeremypw]

OK - it can be left for another PR then.