update docs

[daretodave]

• add notes about history

  • settings
  • file info

• add notes about json viewer

• add notes about file editing

• add notes about context.content API

  • updating content
  • events on content

• add cheatsheet.md

  • add common commands

• add info about utils improve command utilities #107

• add all current system commands

  • missing :relaunch
  • missing :commands

• add info about context.resolve

  • transform from within commannds