NumPy now gives floating point errors in casts
----------------------------------------------

In most cases, NumPy previously did not give floating point
warnings or errors when these happened during casts.
For examples, casts like::

    np.array([2e300]).astype(np.float32)  # overflow for float32
    np.array([np.inf]).astype(np.int64)

Should now generally give floating point warnings.  These warnings
should warn that floating point overflow occurred.
For errors when converting floating point values to integers users
should expect invalid value warnings.

Users can modify the behavior of these warnings using `np.errstate`.

Note that for float to int casts, the exact warnings that are given may
be platform dependend.  For example::

    arr = np.full(100, value=1000, dtype=np.float64)
    arr.astype(np.int8)

May give a result equivalent to (the intermediat means no warning is given)::

    arr.astype(np.int64).astype(np.int8)

May may return an undefined result, with a warning set::

    RuntimeWarning: invalid value encountered in cast

The precise behavior if subject to the C99 standard and its implementation
in both software and hardware.

NumPy now gives floating point errors in casts
----------------------------------------------

In most cases, NumPy previously did not give floating point
warnings or errors when these happened during casts.
For examples, casts like::

    np.array([2e300]).astype(np.float32)  # overflow for float32
    np.array([np.inf]).astype(np.int64)

Should now generally give floating point warnings.  These warnings
should warn that floating point overflow occurred.
For errors when converting floating point values to integers users
should expect invalid value warnings.

Users can modify the behavior of these warnings using `np.errstate`.

Note that for float to int casts, the exact warnings that are given may
be platform dependent.  For example::

    arr = np.full(100, value=1000, dtype=np.float64)
    arr.astype(np.int8)

May give a result equivalent to (the intermediat means no warning is given)::

    arr.astype(np.int64).astype(np.int8)

May return an undefined result, with a warning set::

    RuntimeWarning: invalid value encountered in cast

The precise behavior is subject to the C99 standard and its implementation
in both software and hardware.

Fix typos in upcoming changes
DOC: Fix typos in upcoming changes
