Playground instruction missing carthage build

[simonxcheng]

I found that I need to do carthage build in order to run the playground otherwise I got "no such module" for Result and ReactiveCocoa. Here is the command:
carthage build --verbose --platform OSX

After run this command the error sign is still there but the playground is fine.

[tomj]

hey @simonxcheng did you perform the following steps?:

    1.  Open ReactiveCocoa.xcworkspace
    2.  Build ReactiveCocoa-Mac scheme
    3.  Build Result-Mac scheme
    4.  Finally open the ReactiveCocoa.playground
    5.  Choose View > Show Debug Area

[simonxcheng]

Yes, I did every steps.

[dougbeal]

I ran into the same problem on an unbuilt checkout. I think one of the following is easiest

scripts/bootstrap # OR
carthage checkout

[mdiep]

Would someone like to open a PR to add that to the list of steps?

[tomj]

I'll take care of it, I have a couple of commits cleaning up some typos etc
in the playgrounds which I'll add to it

[tomj]

This is a candidate for closing now that #2930 has been merged