Wiki images fix @https://github.com/goldendict/goldendict/issues/102

1/Fix wiki relative image url
2/Add Custom icon for wiki dic (relative file path : configdir/iconpath
Check for valid icon file
Win-specific: Workaround for CJK Extension B characters handling in QString::toUcs4(). Fix issue #107.
Fix “œ” character for French BGL dictionaries.
increment bgl parser version to reindex existing dictionaries
Support Stardict IFO file encoded with UTF-8. This kind of ifo file is created by StarDict Editor v3.03. Fix issue #42
Update Italian translation. See issue #112
Babylon .bgl: don't encode to utf-8 already encoded articles (tag "<charset c=U>")
Fix show of abbreviations in XDXF dictionaries (issue #116).
Update locale/zh_CN.ts
Tajik Translation Update - Victor Ibragimov - Tajik KDE & Software Localization Team
Tajik Translation Update - Victor Ibragimov - Tajik KDE & Software Localization Team
Merge branch 'tajik'

Conflicts:
	locale/tg_TJ.ts
Merge pull request #119 from tuhaihe/master

update zh_CN translation
Show new translation after group changing
Show decription for XDXF dictionaries
Show decription for AARD dictionaries
Show decription for Stardict dictionaries
Show decription for DSL dictionaries
Lupdate all translations, update Russian translation