UPDATE: Adds 56 functions in the Statistical section

Uses statrs for numerical functions

REFACTOR: Put statistical functions on its own module

This might seem counter-intuitive but the wasm build after this refactor
is 1528 bytes smaller :)

base/src/test/statistical/test_fn_fisher.rs

@@ -0,0 +1,53 @@
+#![allow(clippy::unwrap_used)]
+
+use crate::test::util::new_empty_model;
+#[test]
+fn test_fn_fisher_smoke() {
+    let mut model = new_empty_model();
+
+    // Valid inputs
+    model._set("A1", "=FISHER(0.1)");
+    model._set("A2", "=FISHER(-0.5)");
+    model._set("A3", "=FISHER(0.8)");
+
+    // Domain errors: x <= -1 or x >= 1 -> #NUM!
+    model._set("A4", "=FISHER(1)");
+    model._set("A5", "=FISHER(-1)");
+    model._set("A6", "=FISHER(2)");
+
+    // Wrong number of arguments -> #ERROR!
+    model._set("A7", "=FISHER(0.1, 2)");
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), *"0.100335348");
+    assert_eq!(model._get_text("A2"), *"-0.549306144");
+    assert_eq!(model._get_text("A3"), *"1.098612289");
+
+    assert_eq!(model._get_text("A4"), *"#NUM!");
+    assert_eq!(model._get_text("A5"), *"#NUM!");
+    assert_eq!(model._get_text("A6"), *"#NUM!");
+
+    assert_eq!(model._get_text("A7"), *"#ERROR!");
+}
+
+#[test]
+fn test_fn_fisher_inv_smoke() {
+    let mut model = new_empty_model();
+
+    // Valid inputs
+    model._set("A1", "=FISHERINV(-1.5)");
+    model._set("A2", "=FISHERINV(0.5)");
+    model._set("A3", "=FISHERINV(2)");
+
+    // Wrong number of arguments -> #ERROR!
+    model._set("A4", "=FISHERINV(0.5, 1)");
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), *"-0.905148254");
+    assert_eq!(model._get_text("A2"), *"0.462117157");
+    assert_eq!(model._get_text("A3"), *"0.96402758");
+
+    assert_eq!(model._get_text("A4"), *"#ERROR!");
+}