First 2.x Release

New Features

• Attribute storage is provided by classes implementing the Attribute Interface instead of directly in AttributedString
• New Bitmap class implementing Attribute using a bitmap stored in a string. Very memory efficient.
• BooleanArray class implementing Attribute using a standard PHP array like in AttributedString v1.x. Faster than Bitmap, but uses more than 8x the memory per char length of the string.
• You can inject your own attribute implementations

Incompatible Changes with v1.x

• Unimplemented methods now throw a RuntimeException instead of an InvalidArgumentException