Add tooltip for the values of the change views button in sales grid

[dkamburov]

          I agree with @dkamburov . Let's go with something short and merge. This is not about marketing but to demonstrate more pivot capabilities with a wider variety of pre-defined configurations. The names are not descriptive enough anyway and in the future we are going to be better off having some tooltips explaining what the views show with a few full sentences.

Originally posted by @ChronosSF in #78 (comment)