use 'resource_stream' for compatibility with frozen distributions
Merge branch 'master' into develop
Updated CHANGES and AUTHORS
Simplified certain Quantity related functions and added tests.
Zeros are treated as special values.

See #121 and #122
Skip special value test for array of zeros if NumPy < 1.8

NumPy 1.8 improved the support for binary operations between
a ndarray and a non-ndarray object.

This special case is not supported for older NumPy versions.

See http://docs.scipy.org/doc/numpy/release.html#numpy-1-8-0-release-notes
Fixed NumPy version check
Homogenize behaviour in ScaleConverter, OffsetConverter and Quantity.to

This fixes conversions of delta_temperature

Close #120
Fix test for converter.
Implemented __call__ for UnitRegistry as replacement for []

getitem has been labeled as deprecated and we removed in 0.6.

Close #106
Removed duplicated units/aliases
Raise exception or warn upon redefinition of units.

In the DEFAULT_REGISTRY, an exception (ValueError) is raised.
In any other registry, issue a warning

The behaviour can be chaged using the `on_redefinition` argument in
the constructor.

Close #108
Update nonmultiplicative units docs.
Added docs about serialization.

Closes #109
Fix catching of warnings during testing.
Improved String formatting operations for Measurements

Measurements build upon ufloat from the uncertainties package.
http://pythonhosted.org/uncertainties/

When formatting a Measurement, Pint dispatch formatting codes to
uncertainties to obtain the formatted ufloat.

Close #6
Added test for issue 77 which was fixed when started using uncertainties

Close #77
Issue 77 requires uncertainties.
Improved error messages on faulty definition files. Now most errors are raised instead of logged.
Fixed for Python 2.6 compatibility