Bugfix/copy object bugs

[shino]

This PR fixes a few bugs around PUT Copy / Multipart Upload Copy APIs.

• Fix bugs of the resource value in error response XML when source is
  not existent or not accessible, source bucket/key should be displayed
  there instead of target bucket/key. The bug description is at
  PUT Copy shows target key when source is not found [JIRA: RCS-215] #1169, but this PR does not
  cover error response XML structure compatibility with S3.
• Fix Copy requests without Content-Length request headers (Handling a request has no Content-Length on Upload Part - Copy [JIRA: RCS-187] #939).
  Before this PR, such requests fails with 5xx errors. This PR allows
  requests without CL header in Copy API calls. Additionally, Copy API
  calls with CL more than zero is made to explicitly errors.
• Fix typo bug in upload ID seek, this makes error response of
  unknown upload ID correct (or more understandable.)

[kuenishi]

Rebasing or merging develop needed.

diff --cc riak_test/src/rtcs.erl
index 744446b,dccc445..0000000
--- a/riak_test/src/rtcs.erl
+++ b/riak_test/src/rtcs.erl
@@@ -1013,17 -1020,17 +1020,28 @@@ pbc({multibag, _} = Flavor, ObjectKind
      rtcs_bag:pbc(Flavor, ObjectKind, RiakNodes, Opts).

  make_authorization(Method, Resource, ContentType, Config, Date) ->
++<<<<<<< HEAD
 +    make_authorization(Method, Resource, ContentType, Config, Date, []).
 +
 +%% AmzHeaders are assumed already normalized and sorted
 +make_authorization(Method, Resource, ContentType, Config, Date, AmzHeaders) ->
 +    StsAmzHeaderPart = [[K, $:, V, $\n] || {K, V} <- AmzHeaders],
 +    StringToSign = [Method, $\n, [], $\n, ContentType, $\n, Date, $\n,
 +                    StsAmzHeaderPart, Resource],
 +    lager:debug("StringToSign~n~s~n", [StringToSign]),
++=======
+     make_authorization(s3, Method, Resource, ContentType, Config, Date).
+ 
+ make_authorization(Type, Method, Resource, ContentType, Config, Date) ->
+     StringToSign = [Method, $\n, [], $\n, ContentType, $\n, Date, $\n, Resource],
++>>>>>>> develop
      Signature =
          base64:encode_to_string(sha_mac(Config#aws_config.secret_access_key, StringToSign)),
-     lists:flatten(["AWS ", Config#aws_config.access_key_id, $:, Signature]).
+     Prefix = case Type of
+                  s3 -> "AWS";
+                  velvet -> "MOSS"
+              end,
+     lists:flatten([Prefix, " ", Config#aws_config.access_key_id, $:, Signature]).

[shino]

Rebased on current develop and force pushed.

[kuenishi]

It would be good to have @doc prefix to let edoc know.

[shino]

@borshop merge