Support for members only content

[ktprograms]

Fix: #390

Notes (in no particular order):

• [ ] hasAccessView (green unlocked icon) is a stackview to make it be only the size of the image. Should probably be changed to UIView
• [ ] Sometimes channel claims (for example when searching gifprofile) gets hasAccessView shown. Possibly a race with setting it in ClaimTableViewCell, or it's calling MembershipPerk.perkCheck on channel claims
• [x] Comment stuff (see Slack)
• [x] Text and image content

[ktprograms]

Remaining two points are just minor annoyances (second one is slightly less minor)

@akinwale if you can see why the second point is happening, feel free to fix it. BTW, if it doesn't build for you, it's probably because of the if let syntax I used (Swift 5.7 allows if let variable instead of if let variable = variable, I'm not sure how it works on older Xcode versions). Just replace any if let variable with if let variable = variable. Feel free to modify this PR's branch.

[akinwale]

Remaining two points are just minor annoyances (second one is slightly less minor)

@akinwale if you can see why the second point is happening, feel free to fix it. BTW, if it doesn't build for you, it's probably because of the if let syntax I used (Swift 5.7 allows if let variable instead of if let variable = variable, I'm not sure how it works on older Xcode versions). Just replace any if let variable with if let variable = variable. Feel free to modify this PR's branch.

I'll merge this and create a separate PR to tackle these issues.

[ktprograms]

Done