Add 'features' field in the schema for commands and add a feature flag
to advertise that the fix for savevm [1] is present.

[1] https://lists.gnu.org/archive/html/qemu-devel/2019-09/msg03487.html

v3:
 - added tests
 - mentioned commit fixing savevm in the patch adding the new feature
 - mentioned actual problem in the patch adding the new feature
 - rebased on top of the last batch of Markus' cleanups

Peter Krempa (3):
  qapi: Add feature flags to commands in qapi
  tests: qapi: Test 'features' of commands
  qapi: Allow introspecting fix for savevm's cooperation with blockdev

 docs/devel/qapi-code-gen.txt            |  7 +++---
 qapi/introspect.json                    |  6 ++++-
 qapi/misc.json                          |  9 +++++++-
 scripts/qapi/commands.py                |  3 ++-
 scripts/qapi/doc.py                     |  3 ++-
 scripts/qapi/expr.py                    | 17 ++++++++++++++-
 scripts/qapi/introspect.py              |  7 +++++-
 scripts/qapi/schema.py                  | 22 +++++++++++++++----
 tests/qapi-schema/qapi-schema-test.json | 26 ++++++++++++++++++++++
 tests/qapi-schema/qapi-schema-test.out  | 29 +++++++++++++++++++++++++
 tests/qapi-schema/test-qapi.py          |  7 +++++-
 tests/test-qmp-cmds.c                   | 28 ++++++++++++++++++++++++
 12 files changed, 150 insertions(+), 14 deletions(-)

-- 
2.21.0

I have two simple question on PATCH 2, two straightforward refactorings
to reduce code duplication, and one commit message tweak.

Answer my questions, and then we can decide whether we want a respin or
touch-ups in my tree.

Thanks!