NEW: Bindings for PushStyleVar and PopStyleVar. Thanks @akhleung

NEW: Added imgui.button_arrow(). Thanks @akhleung

FIX: Bug in imgui.color_edit4() when called multiple times.

NEW Added imgui.color_edit4() to show an RGBA color picker

NEW imgui.drag_float()

NEW: imgui.is_window_hovered() by @MrSanShiro

NEW: Added window pivot to set_next_window_pos()

FIX: Check memory allocation when loading font from memory

NEW: Added font glyph ranges option when loading ttf fonts (see imgui.GLYPH_RANGES_CYRILLIC etc)
NEW: Added imgui.add_input_characters() to add one or more UTF8 characters

Updated to support Defold 1.9.0