add a standard library, and introduce formed imports (import std "myfile.pork")

stdlib/src/main/pork/ffi/malloc.pork

@@ -0,0 +1,5 @@
+export func malloc(size)
+  native ffi "c:malloc:void*"
+
+export func free(pointer)
+  native ffi "c:free:void"

stdlib/src/main/pork/numbers.pork

@@ -0,0 +1,15 @@
+export func add(a, b) {
+  a + b
+}
+
+export func subtract(a, b) {
+  a - b
+}
+
+export func multiply(a, b) {
+  a * b
+}
+
+export func divide(a, b) {
+  a / b
+}

stdlib/src/main/pork/stdlib.manifest

@@ -0,0 +1 @@
+numbers.pork