Remove template section from example config
Remove template section from example config

Since our default templates are now compiled into the binary, this is only
relevant to advanced users and will cause trouble when running a derivative
of the example config within the repository directory.
brancz/alertmanager,brunoqc/alertmanager,prometheus/alertmanager,joehandzik/alertmanager,joehandzik/alertmanager,novilabs/alertmanager,prometheus/alertmanager,ericgerling/alertmanager,MonsantoCo/alertmanager,tinytub/alertmanager,novilabs/alertmanager,GoogleCloudPlatform/alertmanager,Aloomaio/alertmanager,brancz/alertmanager,brunoqc/alertmanager,sarathsp06/alertmanager,Kellel/alertmanager,joehandzik/alertmanager,Aloomaio/alertmanager,novilabs/alertmanager,GoogleCloudPlatform/alertmanager,tyrken/alertmanager,tinytub/alertmanager,GoogleCloudPlatform/alertmanager,tyrken/alertmanager,MonsantoCo/alertmanager,Aloomaio/alertmanager,sarathsp06/alertmanager,sarathsp06/alertmanager,tyrken/alertmanager,tinytub/alertmanager,tbouvet/alertmanager,ericgerling/alertmanager,GoogleCloudPlatform/alertmanager,brunoqc/alertmanager,Kellel/alertmanager,MonsantoCo/alertmanager,prometheus/alertmanager,tyrken/alertmanager,ericgerling/alertmanager,MonsantoCo/alertmanager,brunoqc/alertmanager,novilabs/alertmanager,brancz/alertmanager,prometheus/alertmanager,tbouvet/alertmanager,tbouvet/alertmanager,brancz/alertmanager,Kellel/alertmanager