Add basic player pad content type

.idea/encodings.xml

.idea/modules.xml

...de/tobias/playpad/pad/content/AudioPadContentFactory.java

...in/java/de/tobias/playpad/pad/preview/PadTextPreview.java

PlayWallPlugins/PlayWallPluginContentPlayer/pom.xml

...WallPluginContentPlayer/src/main/resources/PadContent.xml

...uginContentPlayer/src/main/resources/lang/base.properties

...nContentPlayer/src/main/resources/lang/base_de.properties

...PlayWallPluginContentPlayer/src/main/resources/plugin.yml

.../de/tobias/playpad/plugin/content/ContentPluginMain.scala

...bias/playpad/plugin/content/player/PlayerPadContent.scala

...aypad/plugin/content/player/PlayerPadContentFactory.scala

...as/playpad/plugin/media/video/VideoPadContentFactory.java

PlayWallPlugins/pom.xml