Feature/news releases (#284)

* added release notes for cadence ui v3.25.0

* adding 3.24.0 release notes to same post

* fixing file name date

* adding java 3.0.0 release

* release notes for cadence server

Author: just-at-uber

news/blog/_posts/2021-04-19-cadence-java-3-0-0.md

@@ -0,0 +1,12 @@
+---
+date: 2021-04-19T07:00:02
+feed:
+  enable: true
+---
+
+# Cadence Java Client v3.0.0
+<release-notes
+  owner="uber"
+  repo="cadence-java-client"
+  tag="v3.0.0"
+/>

news/blog/_posts/2021-04-19-cadence-server-0-20-0.md

@@ -0,0 +1,19 @@
+---
+date: 2021-04-19T07:00:02
+feed:
+  enable: true
+---
+
+## Cadence Server & CLI v0.20.0
+<release-notes
+  owner="uber"
+  repo="cadence"
+  tag="v0.20.0"
+/>
+
+## Cadence Server & CLI v0.19.0
+<release-notes
+  owner="uber"
+  repo="cadence"
+  tag="v0.19.0"
+/>

news/blog/_posts/2021-04-19-cadence-ui-3-25-0.md

@@ -0,0 +1,19 @@
+---
+date: 2021-04-19T07:00:01
+feed:
+  enable: true
+---
+
+## Cadence UI v3.25.0
+<release-notes
+  owner="uber"
+  repo="cadence-web"
+  tag="v3.25.0"
+/>
+
+## Cadence UI v3.24.0
+<release-notes
+  owner="uber"
+  repo="cadence-web"
+  tag="v3.24.0"
+/>