Remove unused methods

o glance/common/utils.py:
  def add_features_to_http_headers(features, headers):

  This method was removed in the following commit.

    commit 76c3620c7effb15be577450c276db1e394c2de3e
    Author: Brian Waldon <bcwaldon@gmail.com>
    Date:   Fri Sep 7 17:21:34 2012 -0700

        Drop Glance Client

  In this case, it has been used only in the following test program.

  - glance/tests/unit/common/test_utils.py

o glance/tests/functional/__init__.py:    def reload_server(self,

  This method was removed in the following commit.

    commit 866cb846f5310e1ad36181e64e7d59ba54d9fd40
    Author: John Bresnahan <jbresnah@redhat.com>
    Date:   Fri May 3 10:50:42 2013 -1000

        Remove glance-control from the test suite

The following methods are not used(w/o tests), however, it can not be
deleted, added the comment.

o glance/common/location_strategy/__init__.py:
  def verify_location_strategy(conf=None,
      strategies=_available_strategies):

Change-Id: I50e3fdb6e929337b946e3534c8e7dbff77ac7998
Fix unsaved exception in store.rbd.Store.add()

When an exception occurs during exception handling, it lose the
information of the first exception.

We should use the excutils.save_and_reraise_exception() in this case.

Change-Id: I1154e17d98804270f9578bc34a5fca6629bd9af4
Closes-Bug: #1292455
Updated from global requirements

Change-Id: I449f493b17e55551f0f7d4f070f6d674f6e5a19a
Merge "Fix unsaved exception in store.rbd.Store.add()"
Merge "Updated from global requirements"
Merge "Remove unused methods"