Complete refactor of project file structure

Fix incorrect handing of default node parameters in SSD subscription.
Fix unable to parse some Clash rule-providers (#289).
Fix not filtering inline comments in some Surge rulesets. (#285)
Add Cron task options.
Add clean context option for persisting a JS context across the whole request.
Replace JS engine with QuickJS.

src/utils/string.h

@@ -0,0 +1,95 @@
+#ifndef STRING_H_INCLUDED
+#define STRING_H_INCLUDED
+
+#include <string>
+#include <sstream>
+#include <vector>
+#include <map>
+
+using string_size = std::string::size_type;
+using string_array = std::vector<std::string>;
+using string_map = std::map<std::string, std::string>;
+using string_pair_array = std::vector<std::pair<std::string, std::string>>;
+
+std::vector<std::string> split(const std::string &s, const std::string &seperator);
+std::string getUrlArg(const std::string &url, const std::string &request);
+std::string replaceAllDistinct(std::string str, const std::string &old_value, const std::string &new_value);
+std::string trimOf(const std::string& str, char target, bool before = true, bool after = true);
+std::string trim(const std::string& str, bool before = true, bool after = true);
+std::string trimQuote(const std::string &str, bool before = true, bool after = true);
+void trimSelfOf(std::string &str, char target, bool before = true, bool after = true);
+std::string trimWhitespace(const std::string &str, bool before = false, bool after = true);
+std::string randomStr(const int len);
+bool isStrUTF8(const std::string &data);
+
+void removeUTF8BOM(std::string &data);
+std::string UTF8ToCodePoint(const std::string &data);
+std::string toLower(const std::string &str);
+std::string toUpper(const std::string &str);
+void processEscapeChar(std::string &str);
+void processEscapeCharReverse(std::string &str);
+int parseCommaKeyValue(const std::string &input, const std::string &separator, string_pair_array &result);
+
+inline bool strFind(const std::string &str, const std::string &target)
+{
+    return str.find(target) != str.npos;
+}
+
+inline bool startsWith(const std::string &hay, const std::string &needle)
+{
+    return hay.substr(0, needle.length()) == needle;
+}
+
+inline bool endsWith(const std::string &hay, const std::string &needle)
+{
+    std::string::size_type hl = hay.length(), nl = needle.length();
+    return hl >= nl && hay.substr(hl - nl, nl) == needle;
+}
+
+inline bool count_least(const std::string &hay, const char needle, size_t cnt)
+{
+    string_size pos = hay.find(needle);
+    while(pos != hay.npos)
+    {
+        cnt--;
+        if(!cnt)
+            return true;
+        pos = hay.find(needle, pos + 1);
+    }
+    return false;
+}
+
+inline char getLineBreak(const std::string &str)
+{
+    return count_least(str, '\n', 1) ? '\n' : '\r';
+}
+
+template <typename T, typename U> static inline T to_number(const U &value, T def_value = T())
+{
+    T retval = 0.0;
+    char c;
+    std::stringstream ss;
+    ss << value;
+    if(!(ss >> retval))
+        return def_value;
+    else if(ss >> c)
+        return def_value;
+    else
+        return retval;
+}
+
+int to_int(const std::string &str, int def_value = 0);
+
+#ifndef HAVE_TO_STRING
+namespace std
+{
+template <typename T> std::string to_string(const T& n)
+{
+    std::ostringstream ss;
+    ss << n;
+    return ss.str();
+}
+}
+#endif // HAVE_TO_STRING
+
+#endif // STRING_H_INCLUDED