Bump pythonclient version to 0.5.2
Bump pythonclient version to 0.5.2

Change-Id: Iace64bfebeccfb21506239089fe8f989a26e3863

DavidPurcell/murano_temp,olivierlemasle/murano,NeCTAR-RC/murano,openstack/murano,satish-avninetworks/murano,ativelkov/murano-api,telefonicaid/murano,sajuptpm/murano,DavidPurcell/murano_temp,telefonicaid/murano,NeCTAR-RC/murano,openstack/murano,olivierlemasle/murano,satish-avninetworks/murano,olivierlemasle/murano,ativelkov/murano-api,satish-avninetworks/murano,DavidPurcell/murano_temp,NeCTAR-RC/murano,NeCTAR-RC/murano,satish-avninetworks/murano,chenyujie/hybrid-murano,DavidPurcell/murano_temp,sergmelikyan/murano,sergmelikyan/murano,sajuptpm/murano,olivierlemasle/murano,chenyujie/hybrid-murano