Fix #978 -- Allow to split names (#1049)

- [x] attendee names
- [x] Invoice address names
- [x] Data migration
- [x] API serializers
  - [x] orderposition
  - [x] cartposition
  - [x] invoiceaddress
  - [x] checkinlistposition
- [x] position API search
- [x] invoice API search
- [x] business/individual required toggle
- [x] Split columns in CSV exports
- [x] ticket editor
- [x] shredder
- [x] ticket/invoice sample data
- [x] order search
- [x] Handle changed naming scheme
- [x] tests
- [x] make use in:
  - [x] Boabee
  - [x] Certificate download order
  - [x] Badge download order
  - [x] Ticket download order
- [x] Document new MySQL requirement
- [x] Plugins

.travis.sh

@@ -11,7 +11,6 @@ fi
 
 if [ "$PRETIX_CONFIG_FILE" == "tests/travis_postgres.cfg" ]; then
     psql -c 'create database travis_ci_test;' -U postgres
-    pip3 install -Ur src/requirements/postgres.txt
 fi
 
 if [ "$1" == "style" ]; then