feat: add seckey

__security/seckey/src/main.rs

@@ -0,0 +1,11 @@
+use seckey::SecBytes;
+
+fn main() {
+    let mut secpass = SecBytes::with(8, |buf| buf.copy_from_slice(&[8; 8][..]));
+    
+    assert_eq!([8u8; 8], *secpass.read());
+
+    let mut wpass = secpass.write();
+    wpass[0] = 0;
+    assert_eq!([0, 8, 8, 8, 8, 8, 8, 8], *wpass);
+}