Use --option <val> instead of --option=val

[tymat]

This fails:

$ ipfs init -b 8192
Error: Could not convert empty value to type 'int' (for option '-b')

This runs

$ ipfs init -b=8192
initializing ipfs node at /Users/tymat/.ipfs
generating 8192-bit RSA keypair...

[jbenet]

thanks @tymat -- found the original issue: #1078 -- closing in favor od that one (may want to subscribe to notifications there)