Modify installation instructions to be compatible with Enarx 0.2.0

Signed-off-by: Paul Pietkiewicz <paul@profian.com>

Author: platten

docs/Installation/Enarx.md

@@ -16,12 +16,12 @@ You can install Enarx from GitHub, crates.io, or Nix.
 
 :::note
 
-Rust version 1.57 is required when installing Enarx 0.1.3 from crates.io.
+Rust version nightly-2022-02-08 is required when installing Enarx 0.2.0 from crates.io.
 
 :::
 
-    $ rustup toolchain install 1.57 -t x86_64-unknown-linux-musl,x86_64-unknown-linux-gnu
-    $ RUSTC_BOOTSTRAP=1 cargo +1.57 install --bin enarx -- enarx
+    $ rustup toolchain install nightly-2022-02-08 -t x86_64-unknown-linux-musl,x86_64-unknown-linux-gnu
+    $ cargo +nightly-2022-02-08 install --bin enarx -- enarx
 
 
 ## Install from Nix

docs/Installation/Setup.md

@@ -66,12 +66,3 @@ Failure to do so might result in weird failures at runtime.
 
     $ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
     $ source $HOME/.cargo/env
-
-
-:::tip 
-
-For Enarx development, Nightly is required:
-
-    $ rustup toolchain install nightly --allow-downgrade -t x86_64-unknown-linux-musl,x86_64-unknown-linux-gnu
-
-:::