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/CallButtons.tsx b/client/src/components/CallButtons.tsx
new file mode 100644
index 0000000..6cc3cb0
--- /dev/null
+++ b/client/src/components/CallButtons.tsx
@@ -0,0 +1,132 @@
+/*
+ * Copyright (C) 2022 Savoir-faire Linux Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program.  If not, see
+ * <https://www.gnu.org/licenses/>.
+ */
+import { IconButton, IconButtonProps } from '@mui/material';
+import { styled } from '@mui/material/styles';
+import React, { useContext } from 'react';
+
+import { CallContext } from '../contexts/CallProvider';
+import { ToggleIconButton, ToggleIconButtonProps } from './Button';
+import {
+  CallEndIcon,
+  ChatBubbleIcon,
+  ExtensionIcon,
+  FullscreenIcon,
+  GroupAddIcon,
+  MicroIcon,
+  MicroOffIcon,
+  RecordingIcon,
+  ScreenShareIcon,
+  VideoCameraIcon,
+  VideoCameraOffIcon,
+  VolumeIcon,
+} from './SvgIcon';
+
+export const CallingChatButton = (props: IconButtonProps) => {
+  return (
+    <IconButton {...props} aria-label="chat" sx={{ color: 'white' }}>
+      <ChatBubbleIcon />
+    </IconButton>
+  );
+};
+export const CallingEndButton = styled((props: IconButtonProps) => {
+  return (
+    <IconButton {...props} aria-label="end call">
+      <CallEndIcon />
+    </IconButton>
+  );
+})(() => ({
+  color: 'white',
+  backgroundColor: 'red',
+  '&:hover': {
+    backgroundColor: 'darkred',
+  },
+}));
+export const CallingExtensionButton = (props: IconButtonProps) => {
+  return (
+    <IconButton {...props} aria-label="extensions" sx={{ color: 'white' }}>
+      <ExtensionIcon />
+    </IconButton>
+  );
+};
+export const CallingFullscreenButton = (props: IconButtonProps) => {
+  return (
+    <IconButton {...props} aria-label="fullscreen" sx={{ color: 'white' }}>
+      <FullscreenIcon />
+    </IconButton>
+  );
+};
+export const CallingGroupButton = (props: IconButtonProps) => {
+  return (
+    <IconButton {...props} aria-label="group options" sx={{ color: 'white' }}>
+      <GroupAddIcon />
+    </IconButton>
+  );
+};
+export const CallingRecordButton = (props: IconButtonProps) => {
+  return (
+    <IconButton {...props} aria-label="recording options" sx={{ color: 'white' }}>
+      <RecordingIcon />
+    </IconButton>
+  );
+};
+export const CallingScreenShareButton = (props: IconButtonProps) => {
+  return (
+    <IconButton {...props} aria-label="screen share" sx={{ color: 'white' }}>
+      <ScreenShareIcon />
+    </IconButton>
+  );
+};
+export const CallingVolumeButton = (props: IconButtonProps) => {
+  return (
+    <IconButton {...props} aria-label="volume options" sx={{ color: 'white' }}>
+      <VolumeIcon />
+    </IconButton>
+  );
+};
+
+export const CallingMicButton = (props: Partial<ToggleIconButtonProps>) => {
+  const { micOn, setMicOn } = useContext(CallContext);
+
+  return (
+    <ToggleIconButton
+      aria-label="microphone options"
+      sx={{ color: 'white' }}
+      IconOn={MicroIcon}
+      IconOff={MicroOffIcon}
+      selected={micOn}
+      toggle={() => setMicOn((s) => !s)}
+      {...props}
+    />
+  );
+};
+
+export const CallingVideoCameraButton = (props: Partial<ToggleIconButtonProps>) => {
+  const { camOn, setCamOn } = useContext(CallContext);
+
+  return (
+    <ToggleIconButton
+      aria-label="camera options"
+      sx={{ color: 'white' }}
+      IconOn={VideoCameraIcon}
+      IconOff={VideoCameraOffIcon}
+      selected={camOn}
+      toggle={() => setCamOn((s) => !s)}
+      {...props}
+    />
+  );
+};