convert from arrays to linked-lists

Signed-off-by: Seth Jennings <sjenning@redhat.com>
add null symbol to inventory files

Add the null symbol to in inventory files.  Before the linked-link
change, the null symbol wasn't included in the inventory.  However,
it is required to be a valid ELF file and should be inventoried and
check for in the test.

Signed-off-by: Seth Jennings <sjenning@redhat.com>
remove temporary debug message

Signed-off-by: Seth Jennings <sjenning@redhat.com>
fixup review comments

Signed-off-by: Seth Jennings <sjenning@redhat.com>
cleanup logic in rela comparison

Per review comments.

Signed-off-by: Seth Jennings <sjenning@redhat.com>
Merge pull request #177 from spartacus06/linked-list

convert core data structures from arrays to linked-lists