updated logo for all static pages

src/main/webapp/accounts/index.html

@@ -16,7 +16,7 @@
 	<div
 		class="d-flex flex-column flex-md-row align-items-center p-3 px-md-4 mb-3 bg-white border-bottom box-shadow">
 		<h5 class="my-0 mr-md-auto font-weight-normal">
-			<img style="width: 65px;" alt="D4Science" src="images/_d4science.png">D4Science
+			<img style="width: 65px;" alt="D4Science" src="images/d4science-logo-sphere.png">D4Science
 			Account
 		</h5>
 		<nav class="my-2 my-md-0 mr-md-3">

src/main/webapp/downtime/index.html

@@ -21,7 +21,7 @@
 	<div class="main-area center-text" style="background-image:url(extra/countdown-6-1600x900.jpg);">
 		<div class="display-table">
 			<div class="display-table-cell">
-					<p><img style="width: 50%;" src="extra/D4Science_logo_600px.png"></p>
+					<p><img style="width: 50%;" src="extra/D4Science-Logo-512px.png"></p>
 				<h1 class="title font-white"><b>We&rsquo;ll be back soon!</b></h1>
 				<p class="desc font-white"><a href="https://www.d4science.org/" target="_blank" style="text-decoration: underline;">The D4Science infrastructure</a> is currently undergoing scheduled maintenance.
 					We Should be back at 6pm CET.<br> Thank you for your patience.</p>

src/main/webapp/smartgears_nodes/templates/index.html.j2

@@ -17,7 +17,7 @@
 	<div
 		class="d-flex flex-column flex-md-row align-items-center p-3 px-md-4 mb-3 bg-white border-bottom box-shadow">
 		<h5 class="my-0 mr-md-auto font-weight-normal">
-			<img style="width: 65px;" alt="D4Science" src="images/_d4science.png">D4Science
+			<img style="width: 65px;" alt="D4Science" src="images/d4science-logo-sphere.png">D4Science
 		</h5>
 		<nav class="my-2 my-md-0 mr-md-3">
 			<a class="p-2 text-dark" href="#">Don't have a D4Science account?</a>

src/main/webapp/support/index.html

@@ -16,7 +16,7 @@
 	<div
 		class="d-flex flex-column flex-md-row align-items-center p-3 px-md-4 mb-3 bg-white border-bottom box-shadow">
 		<h5 class="my-0 mr-md-auto font-weight-normal">
-			<img style="width: 65px;" alt="D4Science" src="images/_d4science.png">D4Science
+			<img style="width: 65px;" alt="D4Science" src="images/d4science-logo-sphere.png">D4Science
 			Help Center
 		</h5>
 		<nav class="my-2 my-md-0 mr-md-3">