`WIP` items in the handbook

[traumschule]

Going forward the council will be more responsible for the handbook. There are several WIP items remaining in these files to expand documentation in coordination with JSG:

system/content-directory/README.md
system/content-directory/nft.md
system/storage/storage-node.md
system/storage/README.md
system/storage/data-directory.md
system/storage/bandwidth-node.md
system/validation.md
system/marketers.md
system/memberships.md
system/builders.md
system/forum.md
system/accounts-and-staking/account-generation.md
system/accounts-and-staking/README.md
.git/hooks/pre-push.sample
.git/objects/pack/pack-61299af5f6feeb60cf06d94f41928b6ddd52e93a.pack
founding-member-program/README.md

Related: #4 #7