Changes some mentions to immutability

Author: patrickfav

README.md

@@ -3,7 +3,7 @@
 Bytes is a utility library that makes it easy to **create**, **parse**, **transform**,
 **validate** and **convert** byte arrays in Java. It's main class `Bytes` is
 a collections of bytes and the main API. It supports [endianness](https://en.wikipedia.org/wiki/Endianness)
-as well as **immutable** and **mutable** access, so the caller may decide to favor
+as well as **copy-on-write** and **mutable** access, so the caller may decide to favor
 performance. This can be seen as combination of the features provided by
 [`BigInteger`](https://docs.oracle.com/javase/7/docs/api/java/math/BigInteger.html),
 [`ByteBuffer`](https://docs.oracle.com/javase/7/docs/api/java/nio/ByteBuffer.html) but
@@ -77,7 +77,7 @@ byte[] result = b.array(); //get as byte array
 
 ## API Description
 
-Per default the instance is **immutable**, which means any transformation will
+Per default the instance is **semi-immutable**, which means any transformation will
 create a copy of the internal array (it is, however, possible to get and
 modify the internal array). There is a **mutable** version which supports
 in-place modification for better performance and a **read-only** version which

src/main/java/at/favre/lib/bytes/Bytes.java

@@ -1440,7 +1440,7 @@ public Bytes byteOrder(ByteOrder byteOrder) {
 
     /**
      * Returns a new read-only byte instance. Read-only means, that there is no direct access to the underlying byte
-     * array and all transformers will create a copy (ie. immutable)
+     * array and all transformers will create a copy.
      *
      * @return a new instance if not already readonly, or "this" otherwise
      */

src/main/java/at/favre/lib/bytes/ReadOnlyBytes.java

@@ -34,7 +34,7 @@
 public final class ReadOnlyBytes extends Bytes {
 
     /**
-     * Creates a new immutable instance
+     * Creates a new read-only instance
      *
      * @param byteArray internal byte array
      * @param byteOrder the internal byte order - this is used to interpret given array, not to change it