v3.1.9

• grpc-gateway was updated to 1.9.5
• grpc-java was updated to 1.22.1
• grpc-web was updated to 1.0.6
• protoc-gen-fieldmask was updated to 0.1.4
• protoc-gen-go was updated to 1.3.2
• protoc-gen-validate was updated to 0.2.0-java
• rust-protobuf was updated to 2.8.0
• Added missing protoc-gen-swagger proto files