Move solana-validator-info into cli (#5768)

* Move solana-validator-info into cli

* Remove solana-validator-info and update docs

* Update test to use app()

cli/src/input_validators.rs

@@ -0,0 +1,36 @@
+use solana_sdk::pubkey::Pubkey;
+use solana_sdk::signature::read_keypair;
+
+// Return an error if a pubkey cannot be parsed.
+pub fn is_pubkey(string: String) -> Result<(), String> {
+    match string.parse::<Pubkey>() {
+        Ok(_) => Ok(()),
+        Err(err) => Err(format!("{:?}", err)),
+    }
+}
+
+// Return an error if a keypair file cannot be parsed.
+pub fn is_keypair(string: String) -> Result<(), String> {
+    read_keypair(&string)
+        .map(|_| ())
+        .map_err(|err| format!("{:?}", err))
+}
+
+// Return an error if string cannot be parsed as pubkey string or keypair file location
+pub fn is_pubkey_or_keypair(string: String) -> Result<(), String> {
+    is_pubkey(string.clone()).or_else(|_| is_keypair(string))
+}
+
+// Return an error if a url cannot be parsed.
+pub fn is_url(string: String) -> Result<(), String> {
+    match url::Url::parse(&string) {
+        Ok(url) => {
+            if url.has_host() {
+                Ok(())
+            } else {
+                Err("no host provided".to_string())
+            }
+        }
+        Err(err) => Err(format!("{:?}", err)),
+    }
+}