Note that jquery.json will be removed in 1.25

This is a pretty straightforward migration, and improves performance
for users with modern browsers (since the skip function means
browsers with native JSON don't need to download a JSON module)

Stating a removal version will encourage this migration.

Change-Id: I8fe83f30fd27f7bfe50e756846486abdadb91189
Merge "Note that jquery.json will be removed in 1.25"