Remove attempt at Fiji-style plugin install

src/ImageJ/install-native/pom.xml

...native/src/main/java/net/leverjs/LeverscJarInstaller.java

...ImageJ/plugin-ij/src/main/java/net/leverjs/LeverscIJ.java

...ij/src/main/java/net/leverjs/LeverscInstallInterface.java

...in-ij/src/main/java/net/leverjs/LeverscInstallLoader.java

src/ImageJ/pom.xml