[BUG #7270] passed only part's class list to lint checking

- instead of entire build class list
[BUG #7270] do extension_match_in also in opts.allowed_globals
[BUG #7270] add config 'exclude' to lint.allowed_globals in compile jobs

- saves a lot of redundant mentionings of classes both in 'exclude' and in
  'lint-check'/'config-warnings'
[BUG #7270] exclude qx.dev.FakeServer, for qx.dev.unit.* dependencies
[BUG #7270] adapt manual to new 'export' config key semantics