Merge pull request #62 from FRidh/standard

IEC 61672 and doc updates to ISO 25417
IEC 61672: Time-averaging and time-weighting
Merge pull request #64 from FRidh/iec

IEC 61672: Time-averaging and time-weighting
Removed unnecessary import
Merge pull request #65 from python-acoustics/import

Removed unnecessary import
Octave: properties
NEW: integrate_bands to change frequency resolution of spectrum.
Force Tox tests against scipy 0.13.3
Merge pull request #69 from felipeacsi/tox-scipy0.13

Force Tox tests against scipy 0.13.3
Merge pull request #68 from FRidh/integrate

NEW: integrate_bands to change frequency resolution of spectrum.
Merge pull request #70 from FRidh/octave

Octave: properties
FIX: Fixes OctaveBand using Octave

Fixes 4fed11e2ca
Merge pull request #71 from FRidh/frequencies

FIX: Fixes OctaveBand using Octave
NEW: easy functions to quickly calculate octave and third-octave levels from signal
Merge pull request #72 from FRidh/octaves

NEW: easy functions to quickly calculate octave and third-octave levels ...
Ignoring emacs and system files
Merge pull request #73 from felipeacsi/gitignore

Ignoring emacs and system files
Functions for all spectra types. Improve octaves/third_octaves
Merge pull request #74 from FRidh/octaves

Functions for all spectra types. Improve octaves/third_octaves
WIP: Generator module

The generator module will consist of classes and tools for generating
signals like noise and waveforms.