[SKCP-84] Added code to store access token offline
[SKCP-84] Added code to store access token offline

InternationalMixMob/CSCI-E-71_IMM_Slacker_Cordova_Plugin,InternationalMixMob/CSCI-E-71_IMM_Slacker_Cordova_Plugin,InternationalMixMob/CSCI-E-71_IMM_Slacker_Cordova_Plugin