* Get rid of unsafe code unless really necessary
* Add lint levels where appropriate
Some crates (air-beautifier, air-testing-framework) have lot of
rust_2018_idioms violations, that will be resolved later.
Testing framework for AquaVM
Its primary features are:
1. It generates services declaratively by annotation in the comments inserted just after calls.
2. Ephemeral network keeps each node's data and incoming data queue. The network can be also generated based on peer IDs featured in the script.
3. One can explicitly add additional peers and services.
The example of the script annotations:
```
(seq
(call "peer_1" ("service" "func") [] var) ; ok=42
(call "peer_2" ("service" "func") [var]) ; err={"ret_code": 1, "result":"no towel"}
)
```
Passing this script to `air_test_framework::TestExecutor::new(...)` will create a virtual network with peers "peer_1" and "peer_2" (and any peer you provide in the `TestRunParameters`), and the particular calls will return respective values.
Please note that autogenerated services use modified service name as a side channel for finding a correct value: "..{N}" is added to each service name (two dots and serial number). Be careful with service names taken from a variable.
* Refactor `avm-server` interface mod to new crate (#294)
The new crate name is `avm-interface`.
It allows to build fully native air-trace, including pure WASM build.
* Make fully native air-trace build
Unless `wasm` feature is enabled (default), fully native build is
produced. You may build WASM air-trace binary with
`cargo build --target wasm32-wasi --no-default-features --release -p air-trace`
* Fix tracing output on native air-trace build
Wrong option was used.
