Add --supported-solc-versions CLI command (#260)

### Description 

Adds `--supported-solc-versions` cli command to return a semver range of
supported `solc` versions.
Is a hack until #162 is implemented.

---------

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

crates/solidity/src/resolc/arguments.rs

@@ -19,6 +19,10 @@ pub struct Arguments {
     #[arg(long = "version")]
     pub version: bool,
 
+    /// Print supported `solc` versions and exit.
+    #[arg(long = "supported-solc-versions")]
+    pub supported_solc_versions: bool,
+
     /// Print the licence and exit.
     #[arg(long = "license")]
     pub license: bool,
@@ -171,6 +175,12 @@ impl Arguments {
             anyhow::bail!("No other options are allowed while getting the compiler version.");
         }
 
+        if self.supported_solc_versions && std::env::args().count() > 2 {
+            anyhow::bail!(
+                "No other options are allowed while getting the supported `solc` versions."
+            );
+        }
+
         #[cfg(debug_assertions)]
         if self.recursive_process_input.is_some() && !self.recursive_process {
             anyhow::bail!("--process-input can be only used when --recursive-process is given");