Add installation step for *.proto files

[jp-pino]

The new ZMQSubscriber and ZMQRepliers in libblunux require a typevals{} list to generate some code at compile time (https://github.com/BluEye-Robotics/libblunux/pull/255). It looks something like:

namespace blunux::zmq {
constexpr inline auto rep_messages =
    utils::typevals{} +
    utils::type_wrapper_2<blueye::protocol::SetOverlayParametersReq,
                          blueye::protocol::SetOverlayParametersRep>{} +
    utils::type_wrapper_2<blueye::protocol::GetOverlayParametersReq,
                          blueye::protocol::GetOverlayParametersRep>{} +
    utils::type_wrapper_2<blueye::protocol::SetCameraParametersReq,
                          blueye::protocol::SetCameraParametersRep>{} +
    utils::type_wrapper_2<blueye::protocol::GetCameraParametersReq,
                          blueye::protocol::GetCameraParametersRep>{} +
    utils::type_wrapper_2<blueye::protocol::SyncTimeReq,
                          blueye::protocol::SyncTimeRep>{} + ...

Managing these lists manually will be a little cumbersome, so I've written a script in libblunux that auto-generates that code based on the .proto files. To make sure we always have them in a consistent location I thought it best to include them in the headers.

The protobuf library itself also does this, installing files like:

• /usr/include/google/protobuf/any.proto
• /usr/include/google/protobuf/field_mask.proto
• /usr/include/google/protobuf/wrappers.proto
• /usr/include/google/protobuf/api.proto
• /usr/include/google/protobuf/descriptor.proto
• /usr/include/google/protobuf/duration.proto
• /usr/include/google/protobuf/source_context.proto
• /usr/include/google/protobuf/struct.proto
• /usr/include/google/protobuf/timestamp.proto
• /usr/include/google/protobuf/empty.proto
• /usr/include/google/protobuf/type.proto

Same with other libraries using protobuf.

They install to the the path .../include/blueyeprotocol/protobuf/*.proto