use Path to represent affected file for consistency with the rest of the library

src/de/uni_passau/fim/seibt/gitwrapper/repo/BlameLine.java

 package de.uni_passau.fim.seibt.gitwrapper.repo;
 
 import java.io.File;
+import java.nio.file.Path;
 import java.util.Collections;
 import java.util.Map;
 
@@ -27,7 +28,7 @@ public class BlameLine {
     /**
      * The file in the commit that the line is attributed to.
      */
-    public final File file;
+    public final Path file;
 
     /**
      * The actual line from the file.
@@ -55,7 +56,7 @@ public class BlameLine {
      * @param otherHeaderFields
      *         other (unrecognized) fields from the 'git blame' commit header
      */
-    private BlameLine(Commit commit, int originalLineNumber, int finalLineNumber, File file, String line,
+    private BlameLine(Commit commit, int originalLineNumber, int finalLineNumber, Path file, String line,
                       Map<String, String> otherHeaderFields) {
 
         this.commit = commit;
@@ -84,7 +85,7 @@ public class BlameLine {
      *         other (unrecognized) fields from the 'git blame' commit header
      * @return a {@link BlameLine} containing the given header fields
      */
-    static BlameLine firstOccurrence(Commit commit, int originalLineNumber, int finalLineNumber, File file, String line,
+    static BlameLine firstOccurrence(Commit commit, int originalLineNumber, int finalLineNumber, Path file, String line,
                                      Map<String, String> otherHeaderFields) {
 
         Map<String, String> other;
@@ -118,7 +119,7 @@ public class BlameLine {
                                     String line) {
 
         Commit commit = firstOccurrence.commit;
-        File file = firstOccurrence.file;
+        Path file = firstOccurrence.file;
         Map<String, String> otherHeaderFields = firstOccurrence.otherHeaderFields;
 
         return new BlameLine(commit, originalLineNumber, finalLineNumber, file, line, otherHeaderFields);

src/de/uni_passau/fim/seibt/gitwrapper/repo/Repository.java

@@ -434,7 +434,7 @@ public class Repository {
             ZoneId authorTZ = null;
             ZoneId committerTZ = null;
 
-            File commitFile = null;
+            Path commitFile = null;
 
             Map<String, String> other = new HashMap<>();
 
@@ -471,7 +471,7 @@ public class Repository {
                         committerTZ = ZoneId.of(lineScanner.next());
                         break;
                     case FILENAME:
-                        commitFile = dir.toPath().resolve(Paths.get(lineScanner.nextLine().trim())).toFile();
+                        commitFile = Paths.get(lineScanner.nextLine().trim());
                         break;
                     case SUMMARY:
                         // We do not explicitly store the summary of the commit as it is just the first line of its message (for which there is a getter).