First steps Builder support

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diff --git a/src/core/lombok/experimental/Builder.java b/src/core/lombok/experimental/Builder.java
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+/*
+ * Copyright (C) 2013 The Project Lombok Authors.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.experimental;
+
+import static java.lang.annotation.ElementType.*;
+import static java.lang.annotation.RetentionPolicy.*;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.Target;
+
+/**
+ * The builder annotation creates a so-called 'builder' aspect to the class that is annotated or the class
+ * that contains a member which is annotated with {@code @Builder}.
+ * <p>
+ * If a member is annotated, it must be either a constructor or a static method. If a class is annotated,
+ * then a private constructor is generated with all fields as arguments
+ * (as if {@code @AllArgsConstructor(AccessLevel.PRIVATE)} is present
+ * on the class), and it is as if this constructor has been annotated with {@code @Builder} instead.
+ * <p>
+ * The effect of {@code @Builder} is that an inner class is generated named <code><strong>T</strong>Builder</code>,
+ * with a private constructor. Instances of <code><strong>T</strong>Builder</code> are made with the static
+ * method named {@code builder()} which is also generated for you in the class itself (not in the builder class).
+ * <p>
+ * The <code><strong>T</strong>Builder</code> class contains 1 method for each parameter of the annotated
+ * constructor / static method (each field, when annotating a class), which returns the builder itself.
+ * The builder also has a <code>build()</code> method which returns a completed instance of the original type,
+ * created by passing all parameters as set via the various other methods in the builder to the constructor
+ * or static method that was annotated with {@code @Builder}. The return type of this method will be the same
+ * as the relevant class, unless a static method has been annotated, in which case it'll be equal to the
+ * return type of that method.
+ * <p>
+ * Complete documentation is found at <a href="http://projectlombok.org/features/experimental/Builder.html">the project lombok features page for &#64;Builder</a>.
+ * <p>
+ * <p>
+ * Before:
+ * 
+ * <pre>
+ * &#064;Builder
+ * class Example {
+ * 	private int foo;
+ * 	private final String bar;
+ * }
+ * </pre>
+ * 
+ * After:
+ * 
+ * <pre>
+ * class Example&lt;T&gt; {
+ * 	private T foo;
+ * 	private final String bar;
+ * 	
+ * 	private Example(T foo, String bar) {
+ * 		this.foo = foo;
+ * 		this.bar = bar;
+ * 	}
+ * 	
+ * 	public static &lt;T&gt; ExampleBuilder&lt;T&gt; builder() {
+ * 		return new ExampleBuilder&lt;T&gt;();
+ * 	}
+ * 	
+ * 	public static class ExampleBuilder&lt;T&gt; {
+ * 		private T foo;
+ * 		private String bar;
+ * 		
+ * 		private ExampleBuilder() {}
+ * 		
+ * 		public ExampleBuilder foo(T foo) {
+ * 			this.foo = foo;
+ * 			return this;
+ * 		}
+ * 		
+ * 		public ExampleBuilder bar(String bar) {
+ * 			this.bar = bar;
+ * 			return this;
+ * 		}
+ * 		
+ * 		&#064;java.lang.Override public String toString() {
+ * 			return "ExampleBuilder(foo = " + foo + ", bar = " + bar + ")";
+ * 		}
+ * 		
+ * 		public Example build() {
+ * 			return new Example(foo, bar);
+ * 		}
+ * 	}
+ * }
+ * </pre>
+ */
+@Target({TYPE, METHOD, CONSTRUCTOR})
+@Retention(SOURCE)
+public @interface Builder {
+	/** Name of the static method that creates a new builder instance. Default: {@code builder}. */
+	String builderMethodName() default "builder";
+}