HashedInputStream.Hasher encapsulates MessageDigest and valid flag,  replaces MessageDigest arg to CachedUrl, BlockHasher, HashedInputStream. Wrap HashedInputStream in BufferedInputStream as filters may call  mark/reset.
HashedInputStream.Hasher encapsulates MessageDigest and valid flag,
 replaces MessageDigest arg to CachedUrl, BlockHasher, HashedInputStream.
Wrap HashedInputStream in BufferedInputStream as filters may call
 mark/reset.


git-svn-id: 293778eaa97c8c94097d610b1bd5133a8f478f36@28989 4f837ed2-42f5-46e7-a7a5-fa17313484d4

lockss/lockss-daemon,lockss/lockss-daemon,edina/lockss-daemon,edina/lockss-daemon,lockss/lockss-daemon,lockss/lockss-daemon,edina/lockss-daemon,edina/lockss-daemon,edina/lockss-daemon,lockss/lockss-daemon,lockss/lockss-daemon,edina/lockss-daemon,lockss/lockss-daemon,edina/lockss-daemon