Add routing for call page

Enable buttons to start a call.
Improve ConversationListItem context menu layout.
Move calling buttons from `Button.tsx` to `CallButtons.tsx`.
Add CallProvider

GitLab: #78
Change-Id: I921aa11383bf39fae18e59b01afb00dc66b0d5e6
diff --git a/client/src/components/SvgIcon.tsx b/client/src/components/SvgIcon.tsx
index 92875b7..d300aa7 100644
--- a/client/src/components/SvgIcon.tsx
+++ b/client/src/components/SvgIcon.tsx
@@ -407,6 +407,33 @@
   );
 };
 
+export const MicroOffIcon = (props: SvgIconProps) => {
+  return (
+    <SvgIcon {...props} viewBox="0 0 24 24">
+      <g>
+        <path
+          d="M12,16.1c1.1,0,2.1-0.4,2.8-1.2c0.8-0.8,1.2-1.9,1.2-2.8V6c0-1.1-0.4-2.1-1.2-2.8c-1.5-1.5-4.2-1.5-5.8,0
+          C8.4,3.8,8,4.9,8,6v6.2c0,1.1,0.4,2.1,1.2,2.8C9.9,15.7,10.8,16.1,12,16.1z M9.4,6c0-0.7,0.3-1.3,0.8-1.9c0.5-0.5,1.1-0.8,1.9-0.8
+          c0.7,0,1.3,0.3,1.9,0.8c0.5,0.5,0.8,1.1,0.8,1.9v6.2c0,0.7-0.3,1.3-0.8,1.9c-1.1,1.1-2.7,1.1-3.6,0c-0.5-0.5-0.8-1.1-0.8-1.9
+          C9.4,12.1,9.4,6,9.4,6z"
+        />
+        <path
+          d="M18.6,8.8c-0.3-0.3-0.7-0.3-1.1,0c0,0.1-0.1,0.3-0.1,0.5v2.8c0,3.1-2.4,5.5-5.5,5.5s-5.5-2.4-5.5-5.5V9.3
+          c0-0.4-0.3-0.7-0.7-0.7l0,0c-0.1-0.1-0.3,0-0.4,0.1C5.1,8.9,5.1,9,5.1,9.3v2.8c0,3.5,2.7,6.4,6.2,6.8v1.7h-2
+          c-0.4,0-0.7,0.3-0.7,0.7c0,0.4,0.3,0.7,0.7,0.7h5.6c0.4,0,0.7-0.3,0.7-0.7c0-0.4-0.3-0.7-0.7-0.7h-2.1V19c3.5-0.4,6.2-3.4,6.2-6.8
+          V9.3C18.9,9,18.9,9,18.6,8.8z"
+        />
+      </g>
+      <g>
+        <path
+          d="M5.5,21.9c-0.1,0-0.3,0-0.4-0.1c-0.3-0.3-0.4-0.7-0.3-1.1L17.7,2.6c0.3-0.3,0.7-0.4,1.1-0.3C19,2.6,19.1,3,19,3.4L6,21.6
+          C5.9,21.8,5.6,21.9,5.5,21.9z"
+        />
+      </g>
+    </SvgIcon>
+  );
+};
+
 export const MicroInBubbleIcon = (props: SvgIconProps) => {
   return (
     <SvgIcon {...props} viewBox="0 0 25 25">
@@ -629,6 +656,24 @@
   );
 };
 
+export const VideoCameraOffIcon = (props: SvgIconProps) => {
+  return (
+    <SvgIcon {...props} viewBox="0 0 24 24">
+      <g id="Icones_Outline" stroke="none" strokeWidth="1" fill="none" fillRule="evenodd">
+        <g id="Camera-Off" stroke="#ffffff" strokeWidth="1.5">
+          <line x1="4.5" y1="18.5" x2="15.5" y2="6.5" id="Line" strokeLinecap="round"></line>
+          <g id="Ico_Camera" transform="translate(3.000000, 5.000000)" fillRule="nonzero" strokeLinejoin="round">
+            <path
+              d="M17.739656,2.05124654 C17.62808,1.97368421 17.4421199,1.93490305 17.1817759,2.0900277 L13.4997675,4.41689751 L13.4997675,1.15927978 C13.4997675,0.849030471 13.3138075,0.5 12.7187355,0.5 L0.929800093,0.5 C0.371920037,0.538781163 0,0.810249307 0,1.19806094 L0,13.8407202 C0,14.2285319 0.371920037,14.5 0.929800093,14.5 L12.7559275,14.5 C13.3138075,14.5 13.5369596,14.1509695 13.5369596,13.8407202 L13.5369596,10.5831025 L17.2189679,12.9487535 C17.4421199,13.1038781 17.62808,13.065097 17.739656,12.9875346 C18,12.83241 18,12.5221607 18,12.4058172 L18,2.63296399 C18,2.5166205 18,2.20637119 17.739656,2.05124654 Z"
+              id="Path"
+            ></path>
+          </g>
+        </g>
+      </g>
+    </SvgIcon>
+  );
+};
+
 export const VolumeIcon = (props: SvgIconProps) => {
   return (
     <SvgIcon {...props} viewBox="0 0 24 24">