Settings page UI + npm installation fixes

views/modals/admin-upgrade.pug

@@ -0,0 +1,25 @@
+.modal(v-bind:class='{ "is-active": upgradeModal.state }')
+  .modal-background
+  .modal-container
+    .modal-content
+      template(v-if='upgradeModal.step === "running"')
+        header.is-blue Install
+        section.modal-loading
+          i
+          span Wiki.js {{ upgradeModal.mode }} in progress...
+          em Please wait
+      template(v-if='upgradeModal.step === "error"')
+        header.is-red Installation Error
+        section.modal-loading
+          span {{ upgradeModal.error }}
+        footer
+          a.button.is-grey.is-outlined(v-on:click='upgradeCancel') Abort
+          a.button.is-deep-orange(v-on:click='upgradeStart') Try Again
+      template(v-if='upgradeModal.step === "confirm"')
+        header.is-deep-orange Are you sure?
+        section
+          label.label You are about to {{ upgradeModal.mode }} Wiki.js.
+          span.note You will not be able to access your wiki during the operation. Content will not be affected. However, it is your responsability to ensure you have a backup in the unexpected event content gets lost or corrupted.
+        footer
+          a.button.is-grey.is-outlined(v-on:click='upgradeCancel') Abort
+          a.button.is-deep-orange(v-on:click='upgradeStart') Start