WAD Rework

Reworked the code for loading and dealing with WAD files. The
code now makes more sense and is much much easier to use. This
should close issue #7.

src/main.rs

@@ -1,7 +1,9 @@
-mod wadutils;
+mod wadfile;
+
+use wadfile::WADFile;
 
 fn main() {
-    let wad_file = wadutils::load_wad("WADs/doom1.wad");
+    let wad_file = WADFile::from_path("WADs/doom1.wad");
 
     println!(
         "WAD Path: {}
@@ -11,11 +13,11 @@ Header:
     Lump Count: {}
     Initial Offset: {}
     Number of Found Lumps: {}",
-        wadutils::get_wad_path(&wad_file),
-        wadutils::get_wad_type(&wad_file),
-        wadutils::get_num_lumps(&wad_file),
-        wadutils::get_init_offset(&wad_file),
-        wadutils::get_directory_len(&wad_file)
+        wad_file.wad_path,
+        wad_file.identifier,
+        wad_file.num_lumps,
+        wad_file.init_offset,
+        wad_file.get_directory_len()
     );
 
     println!("First 15 Directory Entries:");
@@ -24,14 +26,14 @@ Header:
         println!(
             "\t{}\tName {}\tPosition {}\tSize {}",
             i,
-            wadutils::get_lump_name(&wad_file, i),
-            wadutils::get_lump_offset(&wad_file, i),
-            wadutils::get_lump_size(&wad_file, i)
+            wad_file.get_lump_name(i),
+            wad_file.get_lump_offset(i),
+            wad_file.get_lump_size(i)
         );
     }
 
     println!(
         "Index of e1m1 is: {}",
-        wadutils::get_index_from_name(&wad_file, "e1m1").unwrap()
+        wad_file.get_index_from_name("e1m1").unwrap()
     );
 }