Feature: add -c/--content parameter to FSS read programs.

Feature: add -c/--content parameter to FSS read programs.

The default behavior is already a -c/--content.
This provides a literal parameter for good practice and better hackability.

This introduces a new possibility where both -o/--object and -c/--content are specified at the same time.
In this case, print both the object and the content.
It must be noted, however, that this only prints the escaped object and content, just like when -o/--object or -c/--content do already.
The objects in the basic read and extended read are printed with a space between them and their respective content.
The objects in the basic list read and extended list read are printed with an EOL ('\n') between them and their respective content.