[BUGFIX] Issue related to unpredictable UpperCamelCase-to-UpperCamelCase conversion

Internally TYPO3 handles conversion of UCC to UCC (redundant, yes, but can occur!) as "UCC" -> "Ucc" rather than the expected "UCC" -> "UCC". Afterwards, converting "Ucc" to lowercase_underscored of course fails.

Also included is one cleanup commit and one warning message prevention commit.