Parse usage/unallocated.

def _usage_unallocated(raw):
    '''
    Parse usage/unallocated.
    '''
    ret = {}
    for line in raw.split("\n")[1:]:
        keyset = re.sub(r"\s+", " ", line.strip()).split(" ")
        if len(keyset) == 2:
            ret[keyset[0]] = keyset[1]

    return ret