new FT test_theme for theme switcher functionality; theme-switcher content added to home.html, several dashboard views & urls, all appropriate ITs & UTs; lyric user model saves theme (migrations run); django-compressor and django-libsass libraries added to dependencies

src/static_src/scss/core.scss

@@ -0,0 +1,9 @@
+@import 'rootvars';
+
+input,
+textarea,
+select,
+[contenteditable] {
+    user-select: text;
+    touch-action: auto;
+}