Eagerly parse lastpass account data
Eagerly decrypt the password name

This ensures offline logins fail during login instead of when the passwords are first read
Decrypt the fiid and extra fields

fiid == basic auth realm (??)
extra == notes associated with password
Add/update javadoc, make return types consistent
Split non-caching CacheProvider into a NullCacheProvider

Ensure all FileCacheProviders are always caching to a non-null file
Move to using a factory to initialise LastPass

Also modify LastPass's getPasswordStoreBuilder to not take a file,
as this is now handled by LastPassFactory.