using clauses cleanup

src/Yavsc.Abstract/IT/CodeFromChars.cs

@@ -1,6 +1,4 @@
-using System;
 using System.Collections;
-using System.Collections.Generic;
 
 namespace Yavsc.Abstract.IT
 {
@@ -13,10 +11,10 @@ namespace Yavsc.Abstract.IT
 
         }
         public CharArray (IList<char> word): base(word) {
-            
+
         }
         public CharArray (IEnumerable<char> word): base(word) {
-            
+
         }
 
         public IList<char> Aggregate(char other)
@@ -89,10 +87,10 @@ namespace Yavsc.Abstract.IT
                     State = -3;
                     return;
                     }
-                    
+
                 State = states[letter];
 
             }
         }
     }
-}
+}

src/Yavsc.Abstract/IT/ICode.cs

@@ -1,5 +1,3 @@
-using System.Collections.Generic;
-
 namespace Yavsc.Abstract.IT
 {
     // un code est, parmis les ensembles de suites de signes,
@@ -14,7 +12,7 @@ namespace Yavsc.Abstract.IT
         bool Validate();
 
         /// <summary>
-        /// Defines a new letter in this code, 
+        /// Defines a new letter in this code,
         /// as an enumerable of <c>TLetter</c>
         /// </summary>
         /// <param name="letter"></param>

src/Yavsc.Abstract/IT/IProject.cs

@@ -1,5 +1,3 @@
-using System.Collections.Generic;
-
 namespace Yavsc.Abstract.IT
 {
     public interface IProject