Tooltip text descriptions for more entities

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TL;DR

Give more entities a short description text in their tooltips.

What ?

This came up recently when I was playing with people that were very new to the game. They found the tooltips for the first few items quite useful, in particular for figuring out power and complained that they didn't extend to more items in the game. This came up with oil refineries and chemical plants initially. Even a trivial description like e.g. 'oil refineries turn crude oil into petroleum gas and other oil products' can be useful. Pumps in particular need a tooltip that clarifies their function, I know that this is in the description of the technologies but it's easily missable and it should be in the tooltip.