correction to xtract_spectral_inharmonicicty
Merge branch 'master' of https://github.com/jamiebullock/LibXtract
correction to xtract_odd_even_ratio
documentation update
tristimulus1 correction
tristimulus2 correction
tristimulus3 correction
updated docs and removed commented out code
Add "stateful" feature type with initial feature "last n"

Stateful feature extraction functions are functions that require state to be maintained between successive calls.  This is necessary, for example when an accumulation of values is required, or changes need to be measured over time.

The initial xtract_last_n() function accumulates the last N (single) values from *data and writes them to *result
Add xtract_peak() determines whether the 'current' value is a peak
Add ring buffer implementation
Update SWIG bindings, to (for now) ignore new stageful functions
Fix conflict with Makefile.am for SWIG bindings and autotools
Correct name for xtract_peak()
Replace deprecated INCLUDES directive with AM_CFLAGS
Autotools fix: allow subdir-objects
Add stateful.c and ringbuf.c to build system
Merge pull request #53 from seanlikeskites/tristimulusWork

Possible Corrections to Tristimulus Functions
Add stdint include
Add WaveFile class for loading audio files in simpletest