Merge client into next (#1709)

* Merge client
* Add linting script
* Rename serve to start:development
* Move error harmonization and handling to network layer
* Show Comment Stream
* Added initial test

src/core/client/ui/shared/buttonReset.css

@@ -0,0 +1,34 @@
+.buttonReset {
+
+  /* reset button */
+  user-select: none;
+  font-family: inherit;
+  outline: none;
+  border: none;
+  touch-action: manipulation;
+  padding: 0;
+  margin: 0;
+  overflow: hidden;
+
+  /* Unify anchor and button. */
+  cursor: pointer;
+  display: inline-block;
+  box-sizing: border-box;
+  text-align: center;
+  text-decoration: none;
+  align-items: flex-start;
+  vertical-align: middle;
+  white-space: nowrap;
+  background: transparent;
+  font-size: inherit;
+  -webkit-tap-highlight-color: rgba(0, 0, 0, 0) !important;
+
+  &::-moz-focus-inner {
+    border: 0;
+  }
+
+  &:-moz-focusring {
+    color: transparent;
+    textshadow: 0 0 0 #000;
+  }
+}