add correlation and compare support for GROUP sections

GROUP section are rare and are a mechanism in the ELF to indicated that
certain groups of section must be included or excluded (stripped)
together.

It is valid to have more than one of these section with the same
".group" name.  This currently messes up the section correlation code
with correlates based solely on name.

This commit adds additional correlation criteria for GROUP sections;
namely, the section content must be the same.  Changing of groups
sections (i.e. reindexing of the section indexes the GROUP section
includes in their section data) is not supported and will result in a
"new/changed section not included" error.

Signed-off-by: Seth Jennings <sjenning@redhat.com>
cleanup kpatch_correlate_symbols()

This commit inverts some logic to reduce the max indentation

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

Signed-off-by: Seth Jennings <sjenning@redhat.com>
Merge pull request #353 from spartacus06/group-section-support

Group section support