site: Old packages moved from Bintray to Cloudsmith

Since Bintray seized operation, the packages for versions 1.4.0 - 1.8.0
have been uploaded to Cloudsmith. Adjust the links appropriately.

An attribution is added to comply with Cloudsmith's OSS hosting policy.

build.xml

@@ -616,8 +616,7 @@
 					<link name="API Library" src="${gc.url}${currentRelease.tag}/gbapi-${project.releaseVersion}.zip" />
 					<divider />
 					<link name="GitHub (1.9.0+)" src="https://github.com/${gh.org}/gitblit/releases" />
-					<link name="Bintray (1.4.0-1.8.0)" src="https://bintray.com/gitblit/releases/gitblit" />
-					<link name="GoogleCode (pre-1.4.0)" src="https://code.google.com/p/gitblit/downloads/list?can=1" />
+					<link name="Cloudsmith (1.3.0-1.8.0)" src="https://cloudsmith.io/~gitblit/repos/gitblit/groups/" />
 					<divider />
 					<link name="Maven Repository" src="${project.mavenUrl}" />
 				</menu>

src/site/siteindex.mkd

@@ -30,6 +30,8 @@
 		</tbody>
 		</table>
 	</div>
+	<div><a href="https://cloudsmith.com"><img src="https://img.shields.io/badge/OSS%20hosting%20by-cloudsmith-blue?logo=cloudsmith&style=for-the-badge" alt="Hosted By: Cloudsmith"></a><br>
+         Package repository hosting is graciously provided by  <a href="https://cloudsmith.com">Cloudsmith</a>.</div>
 </div>
 
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