Added login method to make sending presence optional (SMACK-52).
Added login method to make sending presence optional (SMACK-52).


git-svn-id: 0d4d1bf2e47502aa0f0957c230a0ec7fa56198fd@2496 b35dd754-fafc-0310-a699-88a17e54d16e

ishan1604/Smack,hy9902/Smack,lovely3x/Smack,ayne/Smack,chuangWu/Smack,vanitasvitae/smack-omemo,Tibo-lg/Smack,xuIcream/Smack,esl/Smack,dpr-odoo/Smack,chuangWu/Smack,deeringc/Smack,vanitasvitae/Smack,ayne/Smack,magnetsystems/message-smack,vito-c/Smack,vito-c/Smack,dpr-odoo/Smack,Flowdalic/Smack,cjpx00008/Smack,ishan1604/Smack,u20024804/Smack,vanitasvitae/smack-omemo,Tibo-lg/Smack,qingsong-xu/Smack,hy9902/Smack,magnetsystems/message-smack,Flowdalic/Smack,hy9902/Smack,esl/Smack,magnetsystems/message-smack,lovely3x/Smack,unisontech/Smack,lovely3x/Smack,igorexax3mal/Smack,kkroid/OnechatSmack,Flowdalic/Smack,igorexax3mal/Smack,unisontech/Smack,xuIcream/Smack,unisontech/Smack,cjpx00008/Smack,vanitasvitae/Smack,deeringc/Smack,u20024804/Smack,qingsong-xu/Smack,esl/Smack,mar-v-in/Smack,vanitasvitae/smack-omemo,igniterealtime/Smack,cjpx00008/Smack,annovanvliet/Smack,opg7371/Smack,mar-v-in/Smack,opg7371/Smack,TTalkIM/Smack,TTalkIM/Smack,qingsong-xu/Smack,igorexax3mal/Smack,andrey42/Smack,chuangWu/Smack,annovanvliet/Smack,ishan1604/Smack,TTalkIM/Smack,u20024804/Smack,mar-v-in/Smack,deeringc/Smack,kkroid/OnechatSmack,andrey42/Smack,kkroid/OnechatSmack,ayne/Smack,igniterealtime/Smack,Tibo-lg/Smack,opg7371/Smack,igniterealtime/Smack,dpr-odoo/Smack,andrey42/Smack,vanitasvitae/Smack,xuIcream/Smack,annovanvliet/Smack