build(wasm): working on getting wasm support into libcomposition

examples/simple.cpp

@@ -0,0 +1,19 @@
+#include "fourdst/composition/composition.h"
+#include "fourdst/atomic/atomicSpecies.h"
+#include "fourdst/atomic/species.h"
+
+#include <unordered_map>
+
+#include <iostream>
+
+int main() {
+
+  std::unordered_map<fourdst::atomic::Species, double> abundances({{fourdst::atomic::H_1, 0.7}, {fourdst::atomic::He_4, 0.28}, {fourdst::atomic::C_12, 0.02}});
+
+  fourdst::composition::Composition comp(abundances);
+
+  std::cout << comp << std::endl;
+
+
+
+}