Travis CI: Force Composer minimum stability <= beta
Travis CI: Force Composer minimum stability <= beta

Unfortunately we must force Composer minimum stability <= beta due to Parsedown 1.8 currently being in beta. Composer AFAIK can't decide this on a per-dependency basis...

PhrozenByte/Pico,TakamiChie/Pico,TakamiChie/Pico,TakamiChie/Pico,picocms/Pico,PhrozenByte/Pico,picocms/Pico,picocms/Pico,TakamiChie/Pico,PhrozenByte/Pico