[TYPO3-core] RFC: Bug #11834: Field handling API in t3lib_extMgm does not check for duplicates on insertion and runs superflouos insertions

[Steffen Kamper]

Hi olly,

+1 by reading und testing. The unit tests and my testextension are 
running successfully.

Additional remark:
* one issue is left, if you add a field to palette that is already 
present as normal field, the field will be rendered and exists 2 times 
in the form. But this should be another RFC.
* what happened to me, if you add a field to palette with position of 
another field, which is also added from extension, it won't work if the 
other extension is loaded after your extension. It's the correct 
behaviour, but the developer doesn't know why it's fail. I suggest a 
syslog message, if a field from configuration doesn't exist in TCA, also 
should be a seperate RFC.

vg Steffen