Updates to open sourcer and heart on your sleeve achievements

[SmashedFrenzy16]

I would suggest splitting out the table of achivements into different categories: Achievable, No Longer Achievable, Unknown

[Schweinepriester]

#698 had this wording

Keep only achievements that are currently obtainable in the achievements list, and open up new sections for "past" achievements e.g. Mars Helicopter 2020, and "upcoming" achievements for those in the planning phase.

[Schweinepriester]

I've experimented in #739, viewable here:
https://github.com/Schweinepriester/github-profile-achievements/tree/Schweinepriester-table-split#achievements
(and the two sections below)

but at this point I'm turned off by how the images are different sizes between tables due to the automatic sizing…

so for now I'd say no, but if the table keeps growing eventually for sure - leaving this issue open!