impl leo build for multiple aleo files

examples/helloworld/imports/other.aleo

@@ -0,0 +1,4 @@
+program other.aleo;
+
+interface other:
+    a as u64;

examples/helloworld/main.aleo

@@ -1,7 +0,0 @@
-program helloworld.aleo;
-
-function main:
-    input r0 as u32.public;
-    input r1 as u32.private;
-    add r0 r1 into r2;
-    output r2 as u32.private;

examples/helloworld/src/imports/other.leo

@@ -0,0 +1,3 @@
+circuit Other {
+    a: u64,
+}