Reorganize sample directory (#34)

This should help keep things organized as speedscope supports more languages & more formats

Test Plan: Try importing from every single file type, see that the link to load the example profile still works

sample/programs/cpp/simple.cpp

@@ -0,0 +1,52 @@
+#include <cstdlib>
+using namespace std;
+
+void leakMemory() {
+  for (int i = 0; i < 100; i++) {
+    malloc(1024);
+  }
+}
+
+void alpha() {
+  leakMemory();
+  int z = 3;
+  for (int i = 0; i < 100000; i++) {
+    z *= 3;
+  }
+}
+
+void beta() {
+  leakMemory();
+  int z = 3;
+  for (int i = 0; i < 100000; i++) {
+    z *= 3;
+  }
+}
+
+void delta() {
+  leakMemory();
+  int z = 3;
+  for (int i = 0; i < 100000; i++) {
+    z *= 3;
+  }
+  alpha();
+  beta();
+}
+
+void gamma() {
+  leakMemory();
+  int z = 3;
+  for (int i = 0; i < 100000; i++) {
+    z *= 3;
+  }
+}
+
+int main(int argc, char* argv[]) {
+  while (true) {
+    alpha();
+    beta();
+    delta();
+    gamma();
+  }
+  return 0;
+}