read.rs: update doc

src/read.rs

@@ -217,12 +217,12 @@ impl Fragments {
         }
     }
 
-    /// create a new pair of Read starting a given chromosome id and position
+    /// create a &str corresponding to a read starting at a given position
     /// # Arguments
     /// - chr_pos: u32 the chromosome position
     /// - first: bool is the sequence for the R1 ?
     /// # Return
-    /// (Read, Read)
+    /// &str
     fn get_seq(&mut self, chr_pos: u32, first: bool) -> &str {
         let mut start = chr_pos;
         let mut end = self.chr_seq.len() as u32;