sample-code: Add some sample Conlang programs :D

sample-code/fibonacci.cl

@@ -0,0 +1,15 @@
+// Calculate Fibonacci numbers
+
+fn main() -> i128 {
+    print("fib(10):");
+    fib(10)
+}
+
+/// Implements the classic recursive definition of fib()
+fn fib(a: i128) -> i128 {
+    if a > 1 {
+        fib(a - 1) + fib(a - 2)
+    } else {
+        1
+    }
+}

sample-code/fizzbuzz.cl

@@ -0,0 +1,20 @@
+// FizzBuzz, using the unstable variadic-`print` builtin
+
+fn main() {
+    fizz_buzz(10, 20)
+}
+
+// Outputs FizzBuzz for numbers between `start` and `end`, inclusive
+fn fizz_buzz(start: i128, end: i128) {
+    for x in start..=end {
+        print(if x % 15 == 0 {
+            "FizzBuzz"
+        } else if 0 == x % 3 {
+            "Fizz"
+        } else if x % 5 == 0 {
+            "Buzz"
+        } else {
+            x
+        })
+    }
+}