PROST version 0.13.0

PROST! is a Protocol Buffers implementation for the Rust Language. prost generates simple, idiomatic Rust code from proto2 and proto3 files.

This major update brings new features and fixes:

Breaking changes

derive Copy trait for messages where possible (#950)

prost-build will automatically derive trait Copy for some messages. If you manually implement Copy you should remove your implementation.
Change generated functions signatures to remove type parameters (#1045)

The function signature of trait Message is changed to use impl Buf instead of a named generic type. If you implement trait Message, you should change the function signature.
Lightweight error value in TryFrom for enums (#1010)

When a impl TryFrom<i32> is generated by prost derive macros, it will now return the error type UnknownEnumValue instead of DecodeError. The new error can be used to retreive the integer value that failed to convert.

fix: Only touch include file if contents is changed (#1058)

Most generated files are untouched when the contents doesn't change. Use the same mechanism for include file as well.

update env_logger requirement from 0.10 to 0.11 (#1074)
update criterion requirement from 0.4 to 0.5 (#1071)
Remove unused libz-sys (#1077)
build(deps): update itertools requirement from >=0.10, <=0.12 to >=0.10, <=0.13 (#1070)