[ADF-112] Change task details feature (due date) (#2071)

* Add Assignee to readonly mode

* Style adoption and first steps to editable mode

* Switch between mode coverage

* Rebase fix

* Because of design and requirement changes, revert unnecessary parts

* Small refactoring before the introduction of CardViewDateItem

* Fix AdfCardView tests

* Editable Card date item

* Do not allow edit on task details after the task is completed.

* Update task details request

* Login footer switch fix

* Login customisable copyright text

* Card text item (first sketches)

* Small fix for supported card items' template

* Dynamic component loading for card view items

* Test and linting fixes

* Updating Readme.md

* Update Readme.md

* Fix Readme.md errors

* CardViewTextItemComponent tests

* Rebase fix

ng2-components/ng2-alfresco-core/src/components/view/adf-card-view-dateitem.component.scss

@@ -0,0 +1,28 @@
+@import 'theming';
+
+.#{$ADF} {
+    &-invisible-date-input {
+        height: 24px;
+        width: 0;
+        overflow: hidden;
+        opacity: 0;
+        border: none;
+        margin: 0;
+        padding: 0;
+    }
+
+    &-dateitem-editable {
+        cursor: pointer;
+
+        button {
+            width: 16px;
+            height: 16px;
+            opacity: 0.5;
+            margin-left: 4px;
+        }
+
+        &:hover button {
+            opacity: 1;
+        }
+    }
+}