Added the public Mesos events calendar to the Community page.
Added the public Mesos events calendar to the Community page.

Review: https://reviews.apache.org/r/40531

yuquanshan/customizedMesos,neilconway/mesos,jpeach/mesos,zmalik/mesos,kaysoky/mesos,verizonlabs/mesos,craimbert/mesos,abudnik/mesos,kaysoky/mesos,reneploetz/mesos,Aman-Jain-14/customizedMesos,Aman-Jain-14/customizedMesos,Gilbert88/mesos,craimbert/mesos,andschwa/mesos,zmalik/mesos,kaysoky/mesos,reneploetz/mesos,dforsyth/mesos,chhsia0/mesos,dforsyth/mesos,dforsyth/mesos,verizonlabs/mesos,gsantovena/mesos,abudnik/mesos,gsantovena/mesos,reneploetz/mesos,jpeach/mesos,Aman-Jain-14/customizedMesos,yuquanshan/customizedMesos,andschwa/mesos,kaysoky/mesos,asamerh4/mesos,zmalik/mesos,andschwa/mesos,jpeach/mesos,andschwa/mesos,Gilbert88/mesos,craimbert/mesos,yuquanshan/customizedMesos,yuquanshan/customizedMesos,zmalik/mesos,reneploetz/mesos,neilconway/mesos,chhsia0/mesos,andschwa/mesos,gsantovena/mesos,kaysoky/mesos,craimbert/mesos,abudnik/mesos,zmalik/mesos,neilconway/mesos,jpeach/mesos,Aman-Jain-14/customizedMesos,Gilbert88/mesos,verizonlabs/mesos,gsantovena/mesos,chhsia0/mesos,neilconway/mesos,neilconway/mesos,asamerh4/mesos,asamerh4/mesos,kaysoky/mesos,andschwa/mesos,abudnik/mesos,asamerh4/mesos,zmalik/mesos,verizonlabs/mesos,jpeach/mesos,craimbert/mesos,gsantovena/mesos,gsantovena/mesos,verizonlabs/mesos,yuquanshan/customizedMesos,dforsyth/mesos,craimbert/mesos,dforsyth/mesos,craimbert/mesos,jpeach/mesos,andschwa/mesos,verizonlabs/mesos,chhsia0/mesos,abudnik/mesos,reneploetz/mesos,zmalik/mesos,yuquanshan/customizedMesos,asamerh4/mesos,Gilbert88/mesos,verizonlabs/mesos,Aman-Jain-14/customizedMesos,chhsia0/mesos,reneploetz/mesos,asamerh4/mesos,Aman-Jain-14/customizedMesos,abudnik/mesos,chhsia0/mesos,abudnik/mesos,neilconway/mesos,chhsia0/mesos,Gilbert88/mesos,gsantovena/mesos,yuquanshan/customizedMesos,Aman-Jain-14/customizedMesos,Gilbert88/mesos,asamerh4/mesos,jpeach/mesos,Gilbert88/mesos,dforsyth/mesos,kaysoky/mesos,reneploetz/mesos,dforsyth/mesos,neilconway/mesos