add internal replacement for boost::split and use it

opm/parser/eclipse/Utility/String.hpp

@@ -3,7 +3,9 @@
 
 #include <algorithm>
 #include <cctype>
+#include <sstream>
 #include <string>
+#include <vector>
 
 namespace Opm {
 
@@ -68,6 +70,39 @@ void replaceAll(T& data, const T& toSearch, const T& replace)
     }
 }
 
+
+inline std::vector<std::string> split_string(const std::string& input,
+                                             char delimiter)
+{
+    std::vector<std::string> result;
+    std::string token;
+    std::istringstream tokenStream(input);
+    while (std::getline(tokenStream, token, delimiter))
+        result.push_back(token);
+
+    return result;
+}
+
+
+inline std::vector<std::string> split_string(const std::string& input,
+                                             const std::string& delimiters)
+{
+    std::vector<std::string> result;
+    std::string::size_type start = 0;
+    while (start < input.size()) {
+        auto end = input.find_first_of(delimiters, start);
+        if (end == std::string::npos) {
+            result.push_back(input.substr(start));
+            end = input.size() - 1;
+        } else if (end != start)
+            result.push_back(input.substr(start, end-start));
+
+        start = end + 1;
+    }
+
+    return result;
+}
+
 }
 
 #endif //OPM_UTILITY_STRING_HPP