[BUG #7279] fixing statements with dotaccessor head symbols

- like qx.Class.define()
[BUG #7279] improved representation of non-library symbols

- the dotted ones
- both internally, for @-hints matching
- as well as for console output
[BUG #7279] a bit of code re-org

- to make sure the top-level Hint() node is properly filled
- and to re-use that code in visit()
[BUG #7279] add skip warning for 'exclude'
[BUG #7279] fixed typo in type
[BUG #7279] add namespace ignores

- this is a 'if(qx.core && qx.core.Environment)'-type appearance of namespaces
- this might look dubious at first as library namespaces are known from the
  library scans
- but *only* if at least one of its contained classes is actually used
  in the build (otherwise they will not be constructed at run time)
- but this is not known at class exploration-time (the class list hasn't been
  settled yet)!
- => it's safer to regard it an unknown global (it cannot be added to the
  build when encountered), and has to be ignored explicitly
[BUG #7279] DEFER_ARGS were not being detected correctly

- as i made 'className' span multiple dots of a composed expression
- make sure only to test the first name part
[BUG #7279] more 'exclude' warning skips for website jobs
[BUG #7279] more re-org for className/classAttribute splitting
[BUG #7279] extend @ignore hint in qx.test.Bootstrap