Refactoring louloulibs and cmake

Use OBJECT libraries
Remove the louloulibs directory
Write FOUND variables in the cache

src/utils/split.cpp

@@ -0,0 +1,19 @@
+#include <utils/split.hpp>
+#include <sstream>
+
+namespace utils
+{
+  std::vector<std::string> split(const std::string& s, const char delim, const bool allow_empty)
+  {
+    std::vector<std::string> ret;
+    std::stringstream ss(s);
+    std::string item;
+    while (std::getline(ss, item, delim))
+      {
+        if (item.empty() && !allow_empty)
+          continue ;
+        ret.emplace_back(std::move(item));
+      }
+    return ret;
+  }
+}