expse paths and fix warnings

src/vcd/parse.rs

@@ -2,7 +2,6 @@
 // This program is distributed under both the GPLV3 license
 // and the YEHOWSHUA license, both of which can be found at
 // the root of the folder containing the sources for this program.
-use std::fs::File;
 
 mod combinator_atoms;
 mod types;