Progress: FSS basic list and extended list.

Progress: FSS basic list and extended list.

Move some common and repeated code into private functions.

Be sure to allow and handle whitespace after a valid object close that is being delimited within content.

Begin adding support for nested in the extended list content write.
- The idea here is to have a whitelist of ranges to ignore.
- This offloads the possible complex logic to a higher level.

The basic and extended list level 2 write functions should both accept a single content instead of an array of content.

Rename the fss write functions, appending _string.
- These functions accept a string instead of an appropriate object/content structure.
- I will need to write the functions that accept the appropriate object/content structures to perform the same tasks.

Make the prepend a constant pointer to make it easier to not specify it (no variable needs to be defined, just pass 0).