Remove deprecated methods supported by neutron_lib

The following methods are now supported in neutron_lib. These have
been marked as depracted in neutron for over a cycle now so we can
remove them:
 - parse_mappings - Use parse_mappings from neutron_lib.utils.helpers
 - get_hostname - Use get_hostname from neutron_lib.utils.net
 - compare_elements - Use compare_elements from neutron_lib.utils.helpers
 - safe_sort_key - Use safe_sort_key from neutron_lib.utils.helpers
 - dict2str - Use dict2str from neutron_lib.utils.helpers
 - str2dict - Use str2dict from neutron_lib.utils.helpers
 - dict2tuple - Use dict2tuple from neutron_lib.utils.helpers
 - diff_list_of_dict - Use diff_list_of_dict from neutron_lib.utils.helpers
 - cpu_count - Use cpu_count from neutron_lib.utils.host
 - round_val - Use round_val from neutron_lib.utils.helpers
 - replace_file - Use replace_file from neutron_lib.utils
 - safe_decode_utf8 - Use safe_decode_utf8 from neutron_lib.utils.helpers

NeutronLibImpact

Change-Id: Ie31da47b34e49a1974ad6b50d9e46ea8e82db294
Partially-implements: blueprint neutron-lib

neutron/common/utils.py

@@ -35,10 +35,7 @@ import eventlet
 from eventlet.green import subprocess
 import netaddr
 from neutron_lib import constants as n_const
-from neutron_lib.utils import file as file_utils
 from neutron_lib.utils import helpers
-from neutron_lib.utils import host
-from neutron_lib.utils import net
 from oslo_concurrency import lockutils
 from oslo_config import cfg
 from oslo_db import exception as db_exc
@@ -97,59 +94,10 @@ def subprocess_popen(args, stdin=None, stdout=None, stderr=None, shell=False,
                             close_fds=close_fds, env=env)
 
 
-@removals.remove(
-    message="Use parse_mappings from neutron_lib.utils.helpers")
-def parse_mappings(mapping_list, unique_values=True, unique_keys=True):
-    return helpers.parse_mappings(mapping_list, unique_values=unique_values,
-                                  unique_keys=unique_keys)
-
-
-@removals.remove(
-    message="Use get_hostname from neutron_lib.utils.net")
-def get_hostname():
-    return net.get_hostname()
-
-
 def get_first_host_ip(net, ip_version):
     return str(netaddr.IPAddress(net.first + 1, ip_version))
 
 
-@removals.remove(
-    message="Use compare_elements from neutron_lib.utils.helpers")
-def compare_elements(a, b):
-    return helpers.compare_elements(a, b)
-
-
-@removals.remove(
-    message="Use safe_sort_key from neutron_lib.utils.helpers")
-def safe_sort_key(value):
-    return helpers.safe_sort_key(value)
-
-
-@removals.remove(
-    message="Use dict2str from neutron_lib.utils.helpers")
-def dict2str(dic):
-    return helpers.dict2str(dic)
-
-
-@removals.remove(
-    message="Use str2dict from neutron_lib.utils.helpers")
-def str2dict(string):
-    return helpers.str2dict(string)
-
-
-@removals.remove(
-    message="Use dict2tuple from neutron_lib.utils.helpers")
-def dict2tuple(d):
-    return helpers.dict2tuple(d)
-
-
-@removals.remove(
-    message="Use diff_list_of_dict from neutron_lib.utils.helpers")
-def diff_list_of_dict(old_list, new_list):
-    return helpers.diff_list_of_dict(old_list, new_list)
-
-
 def is_extension_supported(plugin, ext_alias):
     return ext_alias in getattr(
         plugin, "supported_extension_aliases", [])
@@ -177,12 +125,6 @@ def get_dhcp_agent_device_id(network_id, host):
     return 'dhcp%s-%s' % (host_uuid, network_id)
 
 
-@removals.remove(
-    message="Use cpu_count from neutron_lib.utils.host")
-def cpu_count():
-    return host.cpu_count()
-
-
 class exception_logger(object):
     """Wrap a function and log raised exception
 
@@ -321,18 +263,6 @@ class DelayedStringRenderer(object):
         return str(self.function(*self.args, **self.kwargs))
 
 
-@removals.remove(
-    message="Use round_val from neutron_lib.utils.helpers")
-def round_val(val):
-    return helpers.round_val(val)
-
-
-@removals.remove(
-    message="Use replace_file from neutron_lib.utils")
-def replace_file(file_name, data, file_mode=0o644):
-    file_utils.replace_file(file_name, data, file_mode=file_mode)
-
-
 class _SilentDriverManager(driver.DriverManager):
     """The lamest of hacks to allow us to pass a kwarg to DriverManager parent.
 
@@ -380,12 +310,6 @@ def load_class_by_alias_or_classname(namespace, name):
     return class_to_load
 
 
-@removals.remove(
-    message="Use safe_decode_utf8 from neutron_lib.utils.helpers")
-def safe_decode_utf8(s):
-    return helpers.safe_decode_utf8(s)
-
-
 def _hex_format(port, mask=0):
 
     def hex_str(num):