Improving formatting of functions marked with @property

[sindrehan]

First of all, thank you for a great project! I've used it quite successfully with portray, but when documenting a class that makes quite heavy use of the @property decorator I noticed that the docstring from the setter function is ignored by pdocs. See the example below

class Dummy:
    def __init__(self):
        self._foo = 1
        self._bar = 2

    @property
    def foo(self):
        """Get the value of foo"""
        return self._foo

    @foo.setter
    def foo(self, value):
        """This string is ignored"""
        self._foo = value

    @property
    def bar(self):
        """Get the value of bar"""
        return self._bar

    @bar.setter
    def bar(self, value):
        """This is also ignored"""
        self._bar = value

If possible it would be great to separate the property functions into their own section, with items in the index, etc, similiar to how methods are displayed now.