advotracker: restructure project using crate tree

* advotracker: the framework crate
* crate/advotrackerdb: crate implementing the database backend
* crate/advotrackerd: the backend daemon
* crate/adovtracker: the application (CLI and GUI)

Signed-off-by: Ralf Zerres <ralf.zerres@networkx.de>

crates/advotrackerd/src/lib.rs

@@ -0,0 +1,43 @@
+/*
+ * advotracker - Hotline tackingtool for Advocats
+ *
+ * Copyright 2020 Ralf Zerres <ralf.zerres@networkx.de>
+ * SPDX-License-Identifier: 0BSD, MIT
+ */
+
+#![warn(missing_docs, rust_2018_idioms, rust_2018_compatibility)]
+
+//! advotrackerd: crate documentation
+
+// This function adds two integers (given as arguments) and returns the sum.
+//
+// # Examples
+//
+// ```
+// assert_eq!(8, advotrackerd::internal_adder(4, 4));
+// ```
+fn internal_adder(a: i32, b: i32) -> i32 {
+   a + b
+}
+
+/// This function adds two to its argument.
+///
+/// # Examples
+///
+/// ```
+/// assert_eq!(4, advotrackerd::add_two(2));
+/// ```
+pub fn add_two(a: i32) -> i32 {
+    internal_adder(a, 2)
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn internal_test() {
+	assert_eq!(8, internal_adder(4, 4));
+    }
+}