Increase auto-lock delay to 2 minutes and reset timer on vault access

Auto-lock now happens 2 minutes after the last interaction with
the 1pass client
Fix encryption of item content using 1pass agent

The plaintext was not actually being passed to the agent
for encryption
Add additional docs for functions in vault.go
Add commands to list folder contents and move items to folders
Make folder-pattern argument to 'move' optional

If omitted, the item is removed from its folder
Display item folder info in 'show' output