add walletPrefix to quorum
Create wallet struct

A one atom struct that houses all of the important data to a wallet.
Wallets are kept on disk instead of in memory, because with scripts they
can get very large. Also a participant could theoretically be required
to store 16 million (more realistically just a few thousand).
add encodings from WalletID to walletHandle and back
add testing for id to handle encoding
skip parts of the siacrypto tests during short tests
fix variable types and function names
add Bytes() function to encode wallets to disk
create FillWallet function
add testing to wallet coding
add CreateWallet
flesh out CreateWallet
create wallet in bootstrap, print wallets in Status()
create load script and save script
save files to participantStorage
Merge pull request #135 from DavidVorick/wallets

Adding basic wallets to Sia (closes #114)