Apache Commons Codec 1.7 发布

这是 Commons 项目中用来处理常用的编码方法的工具类包，例如DES、SHA1、MD5、Base64等等。

Apache Commons Codec 1.7 发布，该版本要求 Java 6 的支持。

详细的改进记录包括：

新的特性：
o CODEC-157:  DigestUtils: Add MD2 APIs. Thanks to ggregory.
o CODEC-156:  DigestUtils: add APIs named after standard algorithm name
SHA-1. Thanks to ggregory.
o CODEC-155:  DigestUtils.getDigest(String) should throw
IllegalArgumentException instead of RuntimeException. Thanks to ggregory.
o CODEC-153:  Create a class MessageDigestAlgorithms to define standard
algorithm names. Thanks to ggregory.
o CODEC-152:  DigestUtils.getDigest(String) loses the original exception.
Thanks to ggregory.
o CODEC-151:  Remove unnecessary attempt to fill up the salt variable in
UnixCrypt. Thanks to lathspell.
o CODEC-150:  Remove unnecessary call to Math.abs(). Thanks to lathspell.
o CODEC-148:  More tests and minor things. Thanks to lathspell.
o CODEC-146:  Added regression tests for PhoneticEngine based on
Solr-3.6.0. Thanks to Julius Davies.
o CODEC-139:  DigestUtils: add updateDigest methods and make methods
public. Thanks to dsebastien.
o CODEC-133:  Add classes for MD5/SHA1/SHA-512-based Unix crypt(3) hash
variants. Thanks to lathspell.
o CODEC-130:  Base64InputStream.skip skips underlying stream, not output.
Thanks to tn.
o CODEC-63:   Implement NYSIIS phonetic encoder. Thanks to bayard.

修复Bug:
o CODEC-96:   Base64 encode() method is no longer thread-safe, breaking
clients using it as a shared BinaryEncoder.
              Note: the fix breaks binary compatibility, however the
changes are to a class (BaseNCodec) which is
              intended for internal use. Thanks to sebb.
o CODEC-138:  Complete FilterInputStream interface for
BaseNCodecInputStream.
o CODEC-136:  Use Charset objects when possible, create Charsets for
required character encodings.
o CODEC-132:  BeiderMorseEncoder OOM issues. Thanks to rcmuir.
o CODEC-131:  DoubleMetaphone javadoc contains dead links. Thanks to smolav.

变化：
o CODEC-147:  BeiderMorseEncoder/PhoneticEngine: make results deterministic
by using a LinkedHashSet
              instead of a HashSet.
o CODEC-143:  StringBuffer could be replaced by StringBuilder for local
variables.