Preparing release 0.4.1
Back to development: 0.5
Add links to AUR packages in docs
Updated CHANGES
Removed unnecessary conversion using _to_magnitude.

This is a remnant of the past in which `_to_magnitude` was not used
upon creation.
Store the magnitude when converting to ndarray

When an `__array_` attribute is wanted, it is very likely that was
requested by a NumPy function. We need to convert the magnitude
to an ndarray to obtain the correct, units aware, result.

Previously, the magnitude value was converted to a ndarray and returned,
but the ndarray was not stored in the `_magnitude` attribute.
Very likely, this lead to some unwanted garbage collection.

See #92.
Store the magnitude when converting to ndarray
Use the cache in get_base_units and get_dimensionality. Added benchmarks.
Updated CHANGES
Fix. get_dimensionality should look in the dimensionality cache.
Return copy of base_units and dimensionality to avoid changing the cache.
Improved string_preprocessor. Removed 1cm syntax.

The `1cm` syntax (equivalent to `1*cm`) was broken because it
splited valid names such as `Water_60F` into `Water_60*F`.
While restoring this syntax is possible, it has to handle the
exponential notation. In other words, it should not convert
`1e+24` into `1*e+24`.

Additionally:

- Moved non string_preprocessor tests to a new class.
- Added more tests.
Dimensionality equivalents are only stored for non-prefixed units.

Before this change, the non-prefixed check was done to create the set
but not for adding.

- Fixed representation of Exception warning.
The cache for get_base_units is only for check_nonmult
Fix compatibility with python 2.6
Fix UnicodeWarning when value is not a str (#98)
Update CHANGES

Close #98
Stop raising AttributeError when wrapping funcs

Before Python 3.2, functools.wraps (used in UnitRegistry.wraps) raised
an AttributeError when wrapping functions without all of the attributes
in functools.WRAPPER_ASSIGNMENTS and functools.WRAPPER_UPDATES. In
Python 3.2, this limitation was removed. This commit removes the
limitation in older versions of Python, as well.
Merge branch 'backport-wraps' of git://github.com/jturner314/pint into jturner314-backport-wraps
Updated CHANGES