add support for Github Actions, publish snapshots to OSSRH automatically (#633)

* remove oss-parent

* add github workflow

* use java 16 for now

* disable fail fast

* add java 15

* use only java 8 and 11 for now

* snapshot deploy

* snapshot deploy

* oracle jdk

* oracle jdk

* oracle jdk

* kcms matrix

* kcms job name

* only deploy for snapshots

* try not operator

* prepare PR

* restore groupId

* Fixed Travis link + bonus project summary updates

* Readme improvements

* #629: Preliminary WebP animation (ANIM/ANMF) support

* #629: Fixed build

* Make tests pass on JDK 16 and 17 (#635)

* make tests pass on JDK 16 and 17
replace deprecated mockito-all by mockito-core, and updated to latest 3.x
replace deprecated org.mockito.Matchers

* code cleanup from IDE suggestions

* add oracle jdk 16 and 17 to Travis

* test on java 17

* try to fix warning about maven-source-plugin

Co-authored-by: Harald Kuhr <harald.kuhr@gmail.com>
(cherry picked from commit 191b2371c8)

imageio/imageio-metadata/pom.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
     <parent>
-	<groupId>com.twelvemonkeys.imageio</groupId>        
+	<groupId>com.twelvemonkeys.imageio</groupId>
 	<artifactId>imageio</artifactId>        
         <version>3.8.2-SNAPSHOT</version>
     </parent>