Add charter

[ryjones]

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accidentally approved a wrong PR

[survived]

Thank you @ryjones, we have sent it for approval on our side, I will come back to this once it's done!

[survived]

We've just had discussion about the charter. What we also want to include is that:

1. Some major decisions require 2/3 or 3/4 of TSC votes, like adding or kicking out a TSC member, electing a chair
   1. Nevertheless, if one of TSC member is not responsive (for the period that we should define...) then its vote is not necessary
2. If TSC votes for one of the TSC members and/or maintainer of projects to be kicked out, then all repos maintained by that member/maintainer are transferred out to them (except if that member/maintainer is unresponsive, e.g. in case of bankruptcy, then the repos are maintained by the remaining members)
3. We also want to state that every member of TSC is a company (rather than an individual)

I will look into how I can integrate these changes, preferably without modifying the charter. The charter has some flexibility: e.g. we can define custom structure of the maintainers by documenting them in MAINTAINERS.md, I will look into this further.