issues while building the container

[wschildbach]

I noticed the following problems

• the clone command does not work. It is necessary to use the https:// scheme, not git://
• The postgis container does not start. It complains that pg_ident.conf and pg_hba.conf in volumes/postgis/etc/postgresql/9.6/main are directories instead of files.
• git is not available in the postprocess container, and needs to be installed
• git checkout does not work; it is first necessary to do git config --global --add safe.directory /seesea
• git checkout origin/stevo-dev ./volumes/postprocess/seesea has the wrong path. Try git checkout origin/stevo-dev instead.