Task Description: There are several functions in src/packfile/api.c which are not currently covered by any of our unit tests, and may be dead code. Evaluate them. For each function you find that appears to be uncalled and unused, open a ticket on Parrot Trac to suggest the function be removed. This task is a research task only, you only need to find out if the functions are alive or dead, you do not need to write any code. For some of these, that may require some serious research.

Functions:

1. Parrot_switch_to_cs_by_nr
2. PackFile_Segment_new
3. PackFile_remove_segment_by_name
4. PackFile_Annotations_dump