case-insensitive search was introduced
Some of the REST API's queries seem to be case-insensitive, f. ex.:
https://join-dev.fz-juelich.de:8443/variables/O3
https://join-dev.fz-juelich.de:8443/variables/o3
https://join-dev.fz-juelich.de:8443/contacts/organisations/UBA
https://join-dev.fz-juelich.de:8443/contacts/organisations/uba
https://join-dev.fz-juelich.de:8443/controlled_vocabulary/Role%20Codes
https://join-dev.fz-juelich.de:8443/controlled_vocabulary/role%20codes
Make sure, that this is done for all string comparisons!