rename some variables that collided with imports or (upcoming)
changes, e.g. `ctx`, which is commonly used for `context.Context`.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Older versions of Go don't format comments, so committing this as
a separate commit, so that we can already make these changes before
we upgrade to Go 1.19.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>