use profile class for rights checks
disable some logDebug
add missing global dropdowns frontend
fixes and enhancements about dropdown fields

- change 'global' option to 'isolated' since it was misleading.
- enhance the way fields names/tables/classes are detected when they are
  assigned to object.
disable logdebug
debug GO_FIELDS at init
disable logdebug
secure the way types are loaded

- check for classes existences before registering them.
- minor indentation fixes
fix right naming
remove private on static dbfields
check if classes exists before registering submenus