Add save wallet funciton
Add wallet load funciton
Test wallet save/load
touchups to the client-cli code
get siblings in UploadFile
begin implementation of the client struct
Merge branch 'master' into upload
add Init() to client
add type Keypair to siacrypto
client reorganization
add RSEncode to quorum
address bugs/improvements from PR comments
Merge pull request #162 from DavidVorick/upload

Major Changes to Client
slight tweak to well-tested, segfault-free code
sign entire script input
modify DefaultScript to remove redundant data

Since a signed message includes the original message, it didn't make
sense to append the input to the signed message. The default script
now moves the data pointer to the input inside the signed message.
Merge pull request #163 from lukechampine/scripting

Sign the entire script input
cotinue working on UploadFile
organizational stuff
change MerkleCollapse to a standalone function