[HIPIFY] Scripting related refactoring

+ Move generating hipify-perl and hipify-python into separate namespaces and files
+ Move getAbsoluteFilePath and getAbsoluteDirectoryPath to StringUtils

hipamd/hipify-clang/src/StringUtils.h

@@ -34,3 +34,15 @@ llvm::StringRef unquoteStr(llvm::StringRef s);
   * If `s` starts with `prefix`, remove it. Otherwise, does nothing.
   */
 void removePrefixIfPresent(std::string &s, const std::string& prefix);
+
+/**
+  * Returns Absolute File Path based on filename, otherwise - error.
+  */
+std::string getAbsoluteFilePath(const std::string& sFile, std::error_code& EC);
+
+/**
+  * Returns Absolute Directory Path based on directory name, otherwise - error;
+  * by default the directory is temporary and created.
+  */
+std::string getAbsoluteDirectoryPath(const std::string& sDir, std::error_code& EC,
+  const std::string& sDirType = "temporary", bool bCreateDir = true);