General improvements (#34)

* Minor improvements

* Fix `Debug` implementation

* Fix de-serialization

* Fix accidental usage of nightly

* Fix MSRV warning

* Replace macro with derive-where

* Add `rust-version` into `Cargo.toml`

* Move Serde trait implementation macro to `serialization` module

* Add ability to test without a Ristretto backend

* Improve docs

* Fix testing multiple backends together

* Implement `Ord` and `PartialOrd`

* `no_std` by default

* Remove unnecessary `doc_cfg`

* Remove dev-dependency on self

* Implement `Ord` and `PartialOrd` for `InternalError`

* Remove base64 encoding for serde

* Only take references

* Remove unnecessary qualifications from super-trait times

.github/workflows/main.yml

@@ -37,10 +37,13 @@ jobs:
         backend_feature:
           - ristretto255_u64
           - ristretto255_u32
-          - p256,ristretto255_u64
+          # skip doc tests
+          - p256 --lib
+          - ristretto255_u64,p256
         frontend_feature:
-          - serde
-          - danger
+          -
+          - --features serde
+          - --features danger
         toolchain:
           - stable
           - 1.51.0
@@ -66,7 +69,7 @@ jobs:
         uses: actions-rs/cargo@v1
         with:
           command: test
-          args: --no-default-features --features ${{ matrix.frontend_feature }},std --features ${{ matrix.backend_feature }}
+          args: --no-default-features ${{ matrix.frontend_feature }},std --features ${{ matrix.backend_feature }}
 
   build-no-std:
     name: Build with no-std on ${{ matrix.target }}