Document always returning at least 1 core (#106)

src/lib.rs

@@ -47,6 +47,8 @@ use linux::{get_num_cpus, get_num_physical_cpus};
 /// This function will get the number of logical cores. Sometimes this is different from the number
 /// of physical cores (See [Simultaneous multithreading on Wikipedia][smt]).
 ///
+/// This will always return at least `1`.
+///
 /// # Examples
 ///
 /// ```
@@ -75,6 +77,8 @@ pub fn get() -> usize {
 
 /// Returns the number of physical cores of the current system.
 ///
+/// This will always return at least `1`.
+///
 /// # Note
 ///
 /// Physical count is supported only on Linux, mac OS and Windows platforms.