multiple resolc fixes and improvements (#151)

- Error out early on compiler invocations with invalid base path or include path flags.
- Do not error out if no files and no errors were produced. This aligns resolc closer to sloc.
- Add a CLI test with an involved fixture containing multiple contract remappings to properly testing the standard JSON path.
- Fixes input normalization in the Wasm version.



Co-authored-by: Cyrill Leutwiler <cyrill@parity.io>

crates/solidity/src/solc/soljson_compiler.rs

@@ -35,6 +35,7 @@ impl Compiler for SoljsonCompiler {
         _allow_paths: Option<String>,
     ) -> anyhow::Result<StandardJsonOutput> {
         let version = self.version()?;
+        input.normalize(&version.default);
         let suppressed_warnings = input.suppressed_warnings.take().unwrap_or_default();
 
         let input_json = serde_json::to_string(&input).expect("Always valid");