first version of chunker long description

License: MIT
Signed-off-by: Enrique Erne <enrique.erne@gmail.com>

core/commands/add.go

@@ -71,6 +71,30 @@ its filename. For example:
 You can now refer to the added file in a gateway, like so:
 
   /ipfs/QmaG4FuMqEBnQNn3C8XJ5bpW8kLs7zq2ZXgHptJHbKDDVx/example.jpg
+
+The chunker option, '-s', defines the chunking strategy for how 
+ipfs puts larger files into blocks. Blocks with same content can
+be deduplicated. The default is a fixed block size of
+256 * 1024 bytes, 'size-262144'. A variable block size can be
+specified by using the rabin chunker, rabin-[min]-[avg]-[max].
+Using different chunking strategies will produce different hashes 
+for the same file.
+
+  > ipfs add --chunker=size-1024 ipfs-logo.svg
+  added QmZ9KNxxeeLCPrdceBjvVcmSyLbUWMF4ceKDP8yboLNoHT ipfs-logo.svg
+  > ipfs add --chunker=rabin-128-256-2048 ipfs-logo.svg
+  added QmQN64Mbj1WK8wAej5MoFkHkD3aTtSGzGnAFXomdVHNNhs ipfs-logo.svg
+
+You can now check what blocks have been created by:
+
+  > ipfs object links QmQN64Mbj1WK8wAej5MoFkHkD3aTtSGzGnAFXomdVHNNhs
+  Qmb3Wzsmy9RXkyQhERdPd93mBP2jTRUjgVBwx5yWJR5b6k 223   
+  Qmc7ikMLM1SS88YxxogRtjAyuLLfR85ZDKjfy7ahZYD38h 141   
+  QmeUiJHEXZnEwjpCfUUSkDuXFk2nuT6gALCeUXtZkRvcbj 858   
+  QmWwiQMNhpjq9kFUiuFbSQoqrQNTVjwo1wgbbx8wPr9PjB 1040  
+  QmNPg3SUphwfoJwveDyMRjDDaoitTCE7g9UUqYod8gPwz5 431   
+  QmPzBVWJtMPdeaoJK55rua7LgbEsjHseMHsUSUrPJ3AncS 278   
+  QmQB28iwSriSUSMqG2nXDTLtdPHgWb4rebBrU7Q1j4vxPv 338
 `,
 	},