balance_response: fix bug causing misbalance.

We want to figure out if s is the proper descendant of a local quad, otherwise
we want the list of quads that overlap s.  This bug caused the routine to miss a
case where s is a descendant.
Merge remote branch 'toby/hotfix-balance-bug'
Balance clarifications
Merge remote branch 'toby/hotfix-balance-bug'
Introduce a bug to introduce is_strict_ancestor
Assign the no-empty-tree bug to 0.5
Write bug on distributing connectivity in parallel
Start p4est interface howto document
Create part A figure
Add two pdf files to docs
Use tikz trees
Work on part A and B images and captions
Create third figure
Add figures on AMR pipeline
First shot at interface document
Some usage edits
Another edit and updated pdf doc
p4est_connecitivity_join_faces: limited functionality, compiles.
connect_edges, connect_corners: fixed backwards difference
connect faces: extend to sparser initial connectivity.