solc-json-interface: support for YUL optimizer details (#361)

- Add support for the YUL optimizer details in the standard json input
definition.
- Make optimizer settings optional. They can be omitted and solc will
pick default values ([see here for
reference](https://docs.soliditylang.org/en/latest/using-the-compiler.html#input-description)).

For example allows to use the
[`yul-phaser`](https://github.com/ethereum/solidity/blob/0917604a5ec7cff8bd40a1137f4fcb303fb90527/tools/yulPhaser/README.md?plain=1)
utility. I did a single search with slightly adjusted costs (just made
some educated guess) and after an hour or so this already found an
optimizer sequence
(`OESsShMxeoufcSTvlFxtelTfnfEvicdFxnsvopgCaIeLcnvsTtUrUgdVTUttaeUomccTTTuujsVVvVDvvueUrTjUOmjrrhuuTtj`)
which shrinks the size of the `EndpointV2.sol` from LayerZero by 10%.

---------

Signed-off-by: Cyrill Leutwiler <bigcyrill@hotmail.com>
Signed-off-by: xermicus <cyrill@parity.io>

crates/solc-json-interface/src/standard_json/input/settings/mod.rs

@@ -74,9 +74,9 @@ impl Settings {
     }
 
     /// Sets the necessary defaults.
-    pub fn normalize(&mut self, version: &semver::Version) {
+    pub fn normalize(&mut self) {
         self.polkavm = None;
-        self.optimizer.normalize(version);
+        self.optimizer.normalize();
     }
 
     /// Parses the library list and returns their double hashmap with path and name as keys.