Move writable data out of installation

[jpschewe]

Moving the database and writable directories outside the installation would make it easier to create a Windows installer where the application would be installed in the standard program files and the data lives in the user's home directory. This would also make running inside a container possible.

See #1117 and #567 for references.

[jpschewe]

Current locations of writable data:

• web/WEB-INF/flldb.* -> database
• web/custom -> custom pages to display on the big screen
• web/slideshow -> slideshow images
• web/sponsor_logos - > sponsor logos
• user-images -> replacement logos
• database-backups -> database backups for large changes
• logs/ -> application logs

[jpschewe]

The location of the writable data should be dependent on the port number to avoid conflicts with multiple servers running at the same time.
I need to think about people testing multiple versions of the software running on the default port.

[jpschewe]

I talked to Jeannie about this and we think it's going to be ok.