Context files in volume

https://ufz-rdm.atlassian.net/jira/software/c/projects/TSM/boards/105?selectedIssue=TSM-486

what changed?

• moved tomcat context files from .data/tomcat directory into docker volume
• include index.jsp into Dockerfile image build
• build frost image by default with UID=1000 (same as dispatcher)

Why?

To prevent permission conflicts when creating the context files or mounting the index.jsp into the container if we are using a user with UID!=1000

migration strategy?

Just resave all things. The sta endpoints will be recreated in the volume