initial work on settings modal

src/App.js

src/App.scss

src/App.vue

...ts/mobile_post_status_button/mobile_post_status_button.js

src/components/post_status_modal/post_status_modal.js

src/components/post_status_modal/post_status_modal.vue

src/components/settings_modal/settings_modal.js

src/components/settings_modal/settings_modal.scss

src/components/settings_modal/settings_modal.vue

src/components/settings_modal/tabs/data_import_export.js

src/components/settings_modal/tabs/data_import_export.vue

src/components/settings_modal/tabs/mutes_and_blocks.js

src/components/settings_modal/tabs/mutes_and_blocks.vue

src/components/settings_modal/tabs/notifications.js

src/components/settings_modal/tabs/notifications.vue

src/components/settings_modal/tabs/profile.js

src/components/settings_modal/tabs/profile.scss

src/components/settings_modal/tabs/profile.vue

src/components/settings_modal/tabs/security.js

src/components/settings_modal/tabs/security.vue