simple: suggest time.Time.After, time.Time.Before

[johanbrandhorst]

Examples:

1. Suggest rewrite of

   if x.Sub(y) > 0

   to

   if x.After(y)

2. Suggest rewrite of

   if x.Sub(y) < 0

   to

   if x.Before(y)

Could also suggest !x.After instead of x.Sub(y) <= 0 and vice versa, but it's maybe a little more nuanced.