Fix Bad except clauses order

Invalid is an ancestor class of AutoDiskConfigDisabledByImage.
If we catch Invalid before, the user will be see a wrong message
"Invalid instance image." instead of "Requested Image has automatic
disk resize disabled."

Change-Id: Idb021c7da01ad7a1af07585be527773d14ff2d20
Fix XML UnicodeEncode serialization error

The generic Nova XMLSerializer code will currently attempt
to cast to str the value for all leaf nodes. This patch
ensures that no attempt is made to convert unicode which
can cause a UnicodeEncode error. We don't need to convert
unicode for XML text and regardless we encode to UTF-8 at
a later point.

Change-Id: I8135d2b9a67db62b0eafdd301b7fdb67a5dd72cc
Closes-Bug: #1279172
Removes unused code from wsgi _to_xml_node

Removes support for metadata list_collections and dict_collections
as it is no longer used. Looks like it was last used in the previous
implementation of the Nova API framework (eg before the current V2 one)

Change-Id: I314b13816cdcf51f04926ca9eec67cac765cc893
Open Kilo development

Bump pre-version to 2015.1 to formally open master branch to Kilo
development.

Change-Id: Ib634eb7acb64ff1d7be49852972295074b11557a
Reserve 10 migrations for backports

Reserve 10 migrations so that we have the option of backporting fixes
that include a db migration to the stable/juno branch.  We did this
same thing to allow backports and stable/icehouse in
d65139e6f4885869f80ee510f95f733473c579b6.

The choice of 10 migrations is just a magic number.  We haven't used any
of the 10 reserved in previous stable branches, so 10 seems to be enough.

Implements blueprint backportable-db-migrations-kilo

Change-Id: I3e6d2579b22222e51134e517a97f9daa5855382c
Merge "Open Kilo development"
Merge "Fix XML UnicodeEncode serialization error"
Merge "Removes unused code from wsgi _to_xml_node"
Merge "Fix Bad except clauses order"
Merge "Reserve 10 migrations for backports"