report version and usage messages

add -h|--help usage messages to laminarc and laminard

add a mechanism to compile in a version number, and display the
version in the help messages and in the frontend.

resolves #119

src/resources/index.html

@@ -177,7 +177,7 @@
  </div></template>
 
  <main id="app" style="display: grid; grid-template-rows: auto 1fr auto; height: 100%;">
-  <nav id="nav-top" style="display: grid; grid-template-columns: auto auto 1fr auto; grid-gap: 15px;">
+  <nav id="nav-top" style="display: grid; grid-template-columns: auto auto 1fr auto auto; grid-gap: 15px;">
    <router-link to="/" style="display: grid; grid-auto-flow: column; align-items: center; margin: 5px; font-size: 20px;">
     <img src="icon.png"> {{title}}
    </router-link>
@@ -186,6 +186,7 @@
     <router-link v-for="(crumb,i) in _route.path.slice(1).split('/').slice(1,-1)" :to="_route.path.split('/').slice(0,i+3).join('/')">{{crumb}}</router-link>
    </div>
    <div></div>
+   <span class="version">{{version}}</span>
    <div style="display: grid; align-items: center; padding: 0 15px">
     <a v-on:click="toggleNotifications(!notify)" class="nav-icon" :class="{active:notify}" v-show="supportsNotifications" :title="(notify?'Disable':'Enable')+' notifications'">
      <svg width="18" viewBox="0 0 12 12">

src/resources/js/app.js

@@ -50,6 +50,7 @@ const ServerEventHandler = function() {
           comp.esReconnectInterval = 500;
           // Update html and nav titles
           document.title = comp.$root.title = msg.title;
+          comp.$root.version = msg.version;
           // Calculate clock offset (used by ProgressUpdater)
           comp.$root.clockSkew = msg.time - Math.floor((new Date()).getTime()/1000);
           comp.$root.connected = true;
@@ -726,6 +727,7 @@ new Vue({
   el: '#app',
   data: {
     title: '', // populated by status ws message
+    version: '',
     clockSkew: 0,
     connected: false,
     notify: 'localStorage' in window && localStorage.getItem('showNotifications') == 1

src/resources/style.css

@@ -40,6 +40,12 @@ body {
 #nav-top a       { color: var(--nav-fg); }
 #nav-top a:hover { color: white; text-decoration: none; }
 
+.version {
+ align-self: center;
+ font-size: x-small;
+ color: rgba(255,255,255,0.3);
+}
+
 /* navbar svg icons (enable notifications) */
 .nav-icon            { display: inherit; }
 .nav-icon svg        { fill: var(--nav-fg); stroke: #000; }