Abolish support gem tiers

Just make every support gem accessible from the start instead of having 3 tiers, this greatly broadens the scope of skills that are viable for playing through the campaign.

I have been having a good experience playing through the campaign with my 2nd, 3rd, and 4th characters partly because I farmed a bunch of tier 3 support gems on my main character to use on my new characters.

I understand you don't want it to be overwhelming for new players, but you can alleviate this with the suggested gems section.