ui: update callwidget buttons

- buttons are .css and .ui based.

- .svg used as icons are set in .ui.

- .svg updated, filled circles removed.

- backgrounds and borders are set in .css.

- redundant and no-more-used code in callwidget.cpp/instantmessagingwidget.cpp removed.

Change-Id: I9c52801a49d503c3c6a7dc8df9ae02ff90bb6a67
Tuleap: #148
diff --git a/wizarddialog.cpp b/wizarddialog.cpp
index 5543188..1c33470 100644
--- a/wizarddialog.cpp
+++ b/wizarddialog.cpp
@@ -34,7 +34,7 @@
 
     setFixedSize(this->width(),this->height());
 
-    ui->joinButton->setEnabled(false);
+    ui->wizardButton->setEnabled(false);
 
     QPixmap logo(":/images/logo-ring-standard-coul.png");
     ui->ringLogo->setPixmap(logo.scaledToHeight(100, Qt::SmoothTransformation));
@@ -50,7 +50,7 @@
 WizardDialog::accept()
 {
     ui->label->setText(tr("Please wait while we create your account."));
-    ui->joinButton->setEnabled(false);
+    ui->wizardButton->setEnabled(false);
     ui->usernameEdit->setEnabled(false);
 
     repaint();
@@ -78,7 +78,7 @@
 void
 WizardDialog::on_usernameEdit_textChanged(const QString &arg1)
 {
-    ui->joinButton->setEnabled(!arg1.isEmpty());
+    ui->wizardButton->setEnabled(!arg1.isEmpty());
 }
 
 void