Stardict: Isolate resources stylesheets
FFmpeg: Fix potential crash on some codecs (speex for example)
Dsl: Handle SVG images
Add "Copy Image" option into images context menu
Merge branch 'mdict'

Conflicts:
	mdx.cc
Fix unexpected result using QString::toStdWString() (fix #107 again, QTBUG-25536)

* QString::toStdWString() and QString::toUCS4() will have wrong size when
  QString instances contain non-BMP characters.

Close #320
lupdate all translations; update Simplified Chinese translation
Add an option to enable saving resource files with articles (#321)
Merge pull request #324 from timonwong/save_with_res

Add an option to enable saving resource files with articles (#321)