STORM-1860 Remove obsolete code and file(s) for mesh model upload wizard

doc/contributions.txt

indra/newview/CMakeLists.txt

indra/newview/llfloatermodelpreview.cpp

indra/newview/llfloatermodelpreview.h

indra/newview/llfloatermodelwizard.cpp

indra/newview/llfloatermodelwizard.h

indra/newview/llviewerfloaterreg.cpp

indra/newview/skins/default/xui/da/floater_model_wizard.xml

indra/newview/skins/default/xui/de/floater_model_wizard.xml

indra/newview/skins/default/xui/en/floater_model_wizard.xml

indra/newview/skins/default/xui/es/floater_model_wizard.xml

indra/newview/skins/default/xui/fr/floater_model_wizard.xml

indra/newview/skins/default/xui/it/floater_model_wizard.xml

indra/newview/skins/default/xui/ja/floater_model_wizard.xml

indra/newview/skins/default/xui/pt/floater_model_wizard.xml

indra/newview/skins/default/xui/ru/floater_model_wizard.xml

indra/newview/skins/default/xui/tr/floater_model_wizard.xml