Compile time

I just tried the aws-sdk-ec2 in my workspace. rusoto_ec2 was always the second to last crate and took forever (66s) to build. aws-sdk-ec2 seems to be even worse.

```bash
> cargo +nightly build -Z timings

aws-sdk-ec2 v0.0.8-alpha | 95.8s
rusoto_ec2 v0.46.0 | 66.5s
```

Is compile time something you are going to consider in the future?

Start by reproducing the reported `cargo +nightly build -Z timings` results for `aws-sdk-ec2` and compare them with `rusoto_ec2`, using the versions and timings in the issue. The issue names no source files or tests; completion would require an agreed compile-time target, identified bottlenecks, and timing evidence showing improvement.

Written by the indexing model from the issue text.