Fix NPM code block issue (#1602)

* Init config dir

* Fix solc optimizer

* Fix NPM code block issue

* Extend tests

mythril/ethereum/util.py

@@ -141,7 +141,7 @@ def extract_version(file: str) -> Optional[str]:
     for line in file.split("\n"):
         if "pragma solidity" not in line:
             continue
-        version_line = line
+        version_line = line.rstrip()
         break
     if version_line is None:
         return None

tests/util_tests.py

@@ -7,8 +7,17 @@ test_data = (
     ("pragma solidity 0.5.0\n", ["0.5.0"]),
     ("pragma solidity ^0.4.26\n", ["0.4.26"]),
     ("pragma solidity ^0.6.3;\n", [f"0.6.{x}" for x in range(3, 13)]),
+    ("pragma solidity ^0.6.3              ;\n", [f"0.6.{x}" for x in range(3, 13)]),
     (
-        """pragma solidity >=0.4.0 <0.6.0;
+        "pragma solidity ^0.6.3;                       \n",
+        [f"0.6.{x}" for x in range(3, 13)],
+    ),
+    (
+        "pragma solidity ^0.6.3       ;                       \n",
+        [f"0.6.{x}" for x in range(3, 13)],
+    ),
+    (
+        """pragma solidity >=0.4.0 <0.6.0             ;               
         contract SimpleStorage {
             uint storedData;
             function set(uint x) public {