new api endpoint for creating a question for a session

See merge request !16

change loading strategy for questions w/ answeroptions

See merge request !15

problem with Future.traverse is that it spawns to many Futures, blocks when too many requests come in around the same time

Stresstest

See merge request !14

fix sessionmanagement for slick

do not keep connections to db alive

gatling version 2.x isn't compatible w/ 2.12

Motd

See merge request !13

add tests for session motd

add 2 tests for global motd api

- case classes
- slick table definition
- db tables