Effect of Upper/Lower Case Primitives/Subfiles

[Travis Cobbs]

Don't know how frequent this error is, but I still see many files with it.
I know it is ignored as a fault by DatHeader.
LDPE will let the user know it should be corrected and can autocorrect it.

This is NOT an error in the parts. The LDraw format is case-insensitive. I personally would argue against editing existing parts simply to change the case in their type 1 lines.