gradle cleanEclipse should completely nuke .settings.

Today this will only remove `.settings/org.eclipse.jdt.core.prefs`,
leaving a bunch of stale eclipse configuration everywhere.

.settings/org.eclipse.core.resources.prefs

@@ -1,6 +0,0 @@
-eclipse.preferences.version=1
-encoding//src/main/java=UTF-8
-encoding//src/main/resources=UTF-8
-encoding//src/test/resources=UTF-8
-encoding/<project>=UTF-8
-encoding/rest-api-spec=UTF-8

.settings/org.eclipse.jdt.core.prefs

@@ -1,18 +0,0 @@
-eclipse.preferences.version=1
-org.eclipse.jdt.core.compiler.annotation.inheritNullAnnotations=enabled
-org.eclipse.jdt.core.compiler.annotation.missingNonNullByDefaultAnnotation=ignore
-org.eclipse.jdt.core.compiler.annotation.nullable=org.elasticsearch.common.Nullable
-org.eclipse.jdt.core.compiler.annotation.nullanalysis=enabled
-org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.7
-org.eclipse.jdt.core.compiler.compliance=1.7
-org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
-org.eclipse.jdt.core.compiler.problem.nonnullParameterAnnotationDropped=warning
-org.eclipse.jdt.core.compiler.problem.nullAnnotationInferenceConflict=warning
-org.eclipse.jdt.core.compiler.problem.nullReference=warning
-org.eclipse.jdt.core.compiler.problem.nullSpecViolation=warning
-org.eclipse.jdt.core.compiler.problem.nullUncheckedConversion=warning
-org.eclipse.jdt.core.compiler.problem.potentialNullReference=warning
-org.eclipse.jdt.core.compiler.source=1.7
-org.eclipse.jdt.core.formatter.lineSplit=140
-org.eclipse.jdt.core.formatter.tabulation.char=space
-org.eclipse.jdt.core.formatter.tabulation.size=4

build.gradle

@@ -178,6 +178,11 @@ allprojects {
       }
     }
   }
+  task cleanEclipseSettings(type: Delete) {
+    delete '.settings'
+  }
+  // otherwise .settings is not nuked entirely
+  tasks.cleanEclipse.dependsOn(cleanEclipseSettings)
   // otherwise the eclipse merging is *super confusing*
   tasks.eclipse.dependsOn(cleanEclipse)
 }