Don't crash while trying to parse a diff for binary files, fix BetaHu…

…hn#128

src/git.js

@@ -159,6 +159,8 @@ class Git {
  // split diff into separate entries for separate files. \ndiff --git should be a reliable way to detect the separation, as content of files is always indented
  return `\n${ string }`.split('\ndiff --git').slice(1).reduce((resultDict, fileDiff) => {
  const lines = fileDiff.split('\n')
+ if (lines.length === 0) return resultDict; // ignore binary files
+
  const lastHeaderLineIndex = lines.findIndex((line) => line.startsWith('+++'))
  const plainDiff = lines.slice(lastHeaderLineIndex + 1).join('\n').trim()
  let filePath = ''