1.9.10 speed update to UniFrac

untested, potentially incomplete
1.9.10 UniFrac - massive speed improvement

(still needs testing, benchmark)

CHANGES IN VERSION 1.9.10
-------------------------

USER-VISIBLE CHANGES

	- Massive speed/memory improvement for UniFrac calculations (via
`UniFrac` or `distance`
1.9.10 UniFrac - massive speed improvement

Minor package build adjustments for UniFrac update
1.9.10 UniFrac - Massive speed improvement

import ape::prop.part
1.9.10 UniFrac - Massive speed improvement

Housecleaning - Remove deprecated and non-fast-related internals. Also
rm internals obviated by faster ape-derived C functions.
Allowing Mavericks to Use
Merge pull request #358 from benjjneb/patch-1

Loosen igraph dependency spec to accomodate Mavericks binaries slow-release
Fix indexing in 2-sample edge case
Merge pull request #359 from benjjneb/patch-2

Fix indexing in 2-sample edge case
1.9.10 Add UniFrac unit tests, re-organize tests
1.9.10 UniFrac massive speed improvement, C-code

- Massive speed/memory improvement for UniFrac calculations (via
`UniFrac` or `distance`)

- Added unit-tests for the correctness of UniFrac results (no bugs
detected. results from pycogent)

- Moved all unit tests to tests/testthat as recommended by CRAN
maintainers and testthat doc