Enable InOutOctree to run with 64 bit indexes

[kennyweiss]

The InOutOctree has a max depth of 32 levels due to its dependence on axom::IndexType for the (integer) coordinates of each octree block.

@agcapps reported a problem that a user encountered in the quest in/out query where 32 levels was insufficient to separate the mesh's inside from its outside.

To resolve this, axom's octree class should either:

• Support 64-bit indexes when axom::IndexType == int64
• Add an extra configuration option to allow 64-bit indexes, regardless of the value of axom::IndexType

(or more likely, it should support both of these cases, with a default CoordType of axom::IndexType)

[kennyweiss]

I got this working in PR #298, but with the following warning from @agcapps's user-supplied mesh:

***********************************
[WARNING in line 3051 of file <axom>/src/axom/quest/InOutOctree.hpp]
MESSAGE=Failed Check: data.color() == neighborData.color()
Problem at block {grid pt: (66628576,37828854,16595299); level: 26} with data InOutBlockData{isLeaf: yes, color: White} --- neighbor {grid pt: (66628576,37828855,16595299); level: 26} with data InOutBlockData{isLeaf: yes, color: Black}. 
Neighboring leaves that are not gray must have the same color.
***********************************

***********************************
[WARNING in line 3051 of file <axom>/src/axom/quest/InOutOctree.hpp]
MESSAGE=Failed Check: data.color() == neighborData.color()
Problem at block {grid pt: (66628576,37828855,16595299); level: 26} with data InOutBlockData{isLeaf: yes, color: Black} --- neighbor {grid pt: (66628576,37828854,16595299); level: 26} with data InOutBlockData{isLeaf: yes, color: White}. 
Neighboring leaves that are not gray must have the same color.
***********************************

I'll look into this to see if it is actually a problem.

[kennyweiss]

Reopening this issue until the IndexType for an Octree is runtime-selectable.