message: Use configuration target directory when looking up previous report.
diff: @@ -113,8 +113,7 @@ fn print_missing_lines(config: &Config, result: &TraceMap) {
  fn get_previous_result(config: &Config) -> Option<TraceMap> {
  // Check for previous report
  - if let Some(project_dir) = config.manifest.parent() {
  - let mut report_dir = project_dir.join("target");
  + let mut report_dir = config.target_dir();
  report_dir.push("tarpaulin");
  if report_dir.exists() {
  // is report there?
  @@ -128,9 +127,6 @@ fn get_previous_result(config: &Config) -> Option<TraceMap> {
  .unwrap_or_else(|e| error!("Failed to create report directory: {}", e));
  None
  }
  - } else {
  - None
  - }
  }
  fn print_summary(config: &Config, result: &TraceMap) {
  