Refactor PyPSATopo metrics displayed in tooltips

[ricnogfer]

• Add capital cost and marginal cost information in a multi-link tooltip.
• Display the names of the buses that a multi-link connects to (@BertoGBG).

[ricnogfer]

This issue is solved in 1b615ca and a0911ab.

@BertoGBG, please update pypsatopo to version 0.10.0 and see if multi-links display the names of the buses that they connect to now - thanks!

[BertoGBG]

the capital and marginal cost showed by the tool tip on multilinks must've the correct units (e.g xx/MW or xx/(t/h)) referring to bus0. it is crucial for readability of costs that the unit are correct.

the unit of the carrier for bus zero must be used.

[ricnogfer]

Improved tooltips by changing unit of capital/marginal costs, power/energy time-series, etc…, (displayed in tooltips) of generators, loads and stores to inherit from bus where these are connected to (commit: 3ae1aeb).