update language lists and add item in ui.

leocad.pro

@@ -48,7 +48,7 @@ win32-msvc* {
 	LIBS += -ladvapi32 -lshell32 -lopengl32 -luser32
 } else {
 	PRECOMPILED_HEADER = common/lc_global.h
-	LIBS += -lz
+	LIBS += -lz -lopengl32
 	QMAKE_CXXFLAGS_WARN_ON += -Wno-unused-parameter
 }
 
@@ -80,7 +80,7 @@ APPVEYOR_REPO_COMMIT = $$(APPVEYOR_REPO_COMMIT)
 	}
 }
 
-TSFILES = resources/leocad_cs.ts resources/leocad_de.ts resources/leocad_es.ts resources/leocad_fr.ts resources/leocad_pt.ts resources/leocad_ru.ts resources/leocad_uk.ts
+TSFILES = resources/leocad_cs.ts resources/leocad_de.ts resources/leocad_es.ts resources/leocad_fr.ts resources/leocad_pt.ts resources/leocad_ru.ts resources/leocad_uk.ts resources/leocad_zh_CN.ts
 lrelease.input = TSFILES
 lrelease.output = ${QMAKE_FILE_PATH}/${QMAKE_FILE_BASE}.qm
 lrelease.commands = $$QMAKE_LRELEASE -silent ${QMAKE_FILE_IN} -qm ${QMAKE_FILE_PATH}/${QMAKE_FILE_BASE}.qm
@@ -343,5 +343,5 @@ OTHER_FILES +=
 RESOURCES += leocad.qrc resources/stylesheet/stylesheet.qrc
 
 !win32 {
-	TRANSLATIONS = resources/leocad_cs.ts resources/leocad_de.ts resources/leocad_es.ts resources/leocad_fr.ts resources/leocad_pt.ts resources/leocad_ru.ts resources/leocad_uk.ts
+        TRANSLATIONS = resources/leocad_cs.ts resources/leocad_de.ts resources/leocad_es.ts resources/leocad_fr.ts resources/leocad_pt.ts resources/leocad_ru.ts resources/leocad_uk.ts resources/leocad_zh_CN.ts
 }

qt/lc_qpreferencesdialog.cpp

@@ -16,7 +16,7 @@
 
 static const char* gLanguageLocales[] =
 {
-	"", "cs_CZ", "de_DE", "en_US", "fr_FR", "pt_PT", "es_ES"
+    "", "cs_CZ", "de_DE", "en_US", "fr_FR", "pt_PT", "es_ES", "zh_CN"
 };
 
 lcQPreferencesDialog::lcQPreferencesDialog(QWidget* Parent, lcPreferencesDialogOptions* Options)

qt/lc_qpreferencesdialog.ui

@@ -80,6 +80,11 @@
               <string>Español</string>
              </property>
             </item>
+            <item>
+             <property name="text">
+              <string>简体中文</string>
+             </property>
+            </item>
            </widget>
           </item>
           <item row="2" column="1">