Get rid of most splash warnings in development

src/components/carousel/carousel.jsx

@@ -55,7 +55,7 @@ var Carousel = React.createClass({
                     }
 
                     return (
-                        <Thumbnail key={item.id}
+                        <Thumbnail key={[this.key, item.id].join('.')}
                                    showLoves={this.props.showLoves}
                                    showRemixes={this.props.showRemixes}
                                    type={item.type}

src/components/navigation/www/navigation.jsx

@@ -266,7 +266,7 @@ var Navigation = React.createClass({
                                         </a>
                                     </li>
                                     {this.props.permissions.educator ? [
-                                        <li>
+                                        <li key="my-classes-li">
                                             <a href="/educators/classes/">
                                                 <FormattedMessage id="general.myClasses" />
                                             </a>

src/components/teacher-banner/teacher-banner.jsx

@@ -35,11 +35,11 @@ var TeacherBanner = React.createClass({
                     <div className="welcome">
                         {this.props.session.status === sessionActions.Status.FETCHED ? (
                             this.props.session.session.user ? [
-                                <h3>
+                                <h3 key="greeting">
                                     {this.props.messages['teacherbanner.greeting']},{' '}
                                     {this.props.session.session.user.username}
                                 </h3>,
-                                <p>
+                                <p key="subgreeting">
                                     {this.props.messages['teacherbanner.subgreeting']}
                                 </p>
                             ] : []
@@ -48,17 +48,17 @@ var TeacherBanner = React.createClass({
                     <FlexRow className="quick-links">
                         {this.props.session.status === sessionActions.Status.FETCHED ? (
                             this.props.session.session.user ? [
-                                <a href="/educators/classes">
+                                <a href="/educators/classes" key="classes-button">
                                     <Button>
                                         {this.props.messages['teacherbanner.classesButton']}
                                     </Button>
                                 </a>,
-                                <a href="/info/educators">
+                                <a href="/info/educators" key="resources-button">
                                     <Button>
                                         {this.props.messages['teacherbanner.resourcesButton']}
                                     </Button>
                                 </a>,
-                                <a href="/educators/faq">
+                                <a href="/educators/faq" key="faq-button">
                                     <Button>
                                         {this.props.messages['teacherbanner.faqButton']}
                                     </Button>

src/views/splash/splash.jsx

@@ -377,7 +377,7 @@ var Splash = injectIntl(React.createClass({
                     </Modal>
                 ] : []}
                 {this.props.permissions.educator ? [
-                    <TeacherBanner messages={messages} />
+                    <TeacherBanner key="teacherbanner" messages={messages} />
                 ] : []}
                 <div key="inner" className="inner">
                     {this.props.session.status === sessionActions.Status.FETCHED ? (