Open invitation setting

Closes #64

pkg/template/pages/admin_settings.html

@@ -33,6 +33,8 @@
 						{{ end }}
 						</select>
 						<input class="form-control form-control-xlarge" type="text" name="Domain" value="{{.Settings.Domain}}" />
+						<label>Open invitations:</label>
+						<input class="form-control form-control-xlarge" type="checkbox" name="OpenInvitations" {{ if .Settings.OpenInvitations }} checked {{ end }} /> enable open invintation requests from users
 					</div>
 					<div class="form-group">
 						<div class="alert">GitHub OAuth Consumer Key and Secret</div>

pkg/template/pages/login.html

@@ -10,6 +10,9 @@
 		<input type="submit" value="Sign in" />
 	</div>
 	<div>
+        {{ if .Settings.OpenInvitations }}
+        <a href="/signup">request invitation</a>&nbsp;
+        {{ end }}
 		<a href="/forgot">forgot password</a>
 	</div>
 {{ end }}

pkg/template/pages/signup.html

@@ -0,0 +1,51 @@
+{{ define "title" }}Sign up · drone.io{{ end }}
+
+{{ define "content" }}
+	<h1>Sign up</h1>
+	<form action="/signup" method="POST" role="form">
+		<div>
+			<input type="text" name="email" placeholder="Email address" autocomplete="off" spellcheck="false" class="form-control" />
+		</div>
+		<div>
+			<div class="alert alert-success hide" id="successAlert"></div>
+			<div class="alert alert-error hide" id="failureAlert"></div>
+		</div>
+		<div>
+			<input type="submit" id="submitButton" value="Request invite" />
+		</div>
+    </form>
+{{ end }}
+
+{{ define "script" }}
+<script>
+		document.forms[0].onsubmit = function(event) {
+
+			$("#successAlert").hide();
+			$("#failureAlert").hide();
+			$('#submitButton').button('loading');
+
+			var form = event.target
+			var formData = new FormData(form);
+			xhr = new XMLHttpRequest();
+			xhr.open('POST', form.action);
+			xhr.onload = function() {
+					if (this.status == 200) {
+							var msg = "User Invitation was sent successfully";
+							if (this.responseText != "OK") {
+									msg = "Email is not currently enabled.  In order to invite the user, you'll need to provide them the following link:<br><span class='url'>" + this.responseText + "</span>";
+							}
+							$("#successAlert").html(msg);
+							$("#successAlert").show().removeClass("hide");
+							$('#submitButton').button('reset')
+
+					} else {
+							$("#failureAlert").text("Failed to send Invitation Email. " + this.response);
+							$("#failureAlert").show().removeClass("hide");
+							$('#submitButton').button('reset')
+					};
+			};
+			xhr.send(formData);
+			return false;
+				}
+	</script>
+{{ end }}

pkg/template/template.go

@@ -45,6 +45,7 @@ func init() {
 		"forgot.html",
 		"forgot_sent.html",
 		"reset.html",
+		"signup.html",
 		"register.html",
 		"install.html",