Rework vehicle signals support to use KUKSA.val databroker

Rework the VehicleSignals class and its use in the Navigation and
Hvac classes to switch from using the original KUKSA.val server
via WebSockets to the KUKSA.val databroker's gRPC "VAL" API.

Notable changes:
- The VehicleSignals API has changed a bit with respect to setting
  signals, callers now need to pass the new value as the type that
  matches the signal as opposed to always passing a string, and
  optionally indicate if an actuator's target or value is being set.
  Subscribe operations now also allow subscribing for either
  actuator targets or values.
- It is possible that the values returned by get and subscribe
  operations will be changed to using QVariant instead of QStrings
  in a future follow up, but that has not been done in these changes.
- The connected signal from VehicleSignals still has roughly the
  same meaning, but the authorize function and authorized signals
  are to some degree redundant now.  They have been kept for
  compatibility, but may be removed in a follow up set of changes.
- The section header in the .ini files expected by the
  VehicleSignalsConfig class has been changed from "vis-client" to
  "kuksa-client" since the databroker is not a VIS server, and to
  some degree forcing an update on the part of clients is useful
  since their authorization tokens also need to change.
- The client key and certificate support has been removed from the
  VehicleSignalsConfig class, as they are no longer used in either
  the server or databroker as of KUKSA.val 0.4.0.  A new optional
  parameter, "tls-server-name", has been added to work with the new
  TLS support behavior.  It can be used to override the expected
  host name for connecting to a non-local databroker instance.
- The Navigation constructor now takes an additional parameter to
  indicate whether the instance acts as a router or a client.
  The underlying need for this stems from an application acting as
  a router needing to subscribe to the destination setting actuator
  targets.

Bug-AGL: SPEC-4762

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: I253480ae2abf068dc6e41a495454960ed5c0feaf

1 files changed, 1 insertions, 0 deletions

diff --git a/meson_options.txt b/meson_options.txt
new file mode 100644
index 0000000..1fe219e
--- /dev/null
+++ b/meson_options.txt
@@ -0,0 +1 @@
+option('protos', type : 'string', value : '/usr/include', description : 'Include directory for .proto files')