Symlinks don't appear in containerPaths

[nightlark]

symlinks don't result in additional entries being added to the containerPath list, only the installPath list. Not sure if this is a bug or correct as is... it's unclear if symlinks are "contained" in an archive/installer/container or not, or more of a process that happens as a result of extracting/installing the contents?

Including them as containerPaths would probably require:

• Tweak the data structure(s) that stores file (and directory?) symlinks to store the relative file path, instead of the final install path with the install prefix prepended
• Track what install prefix to use with each symlink that gets stored
• Track what parent archive UUID to use with each symlink that gets stored

Some of these things may be easier after the restructuring work on the internal representation to be a tree/graph data structure instead.