* Moves `-f` and `--file` to _before_ the command. The wallet file
option is considered a global option which needs to preceed the
command.
* Adds a new global option `--format` which specifies the output
format of a given command. The supported output formats are:
* `table` (default) - The existing visual table output
* `json` - A json form of the output of the command
The `json` form is handy for scripts wrapping the wallet commands
* Removes the `--hash` option for the `pay` command since the
`--format json` output gives the equivalent information and more
* Removes the short version of the `--hashlock` and `--timelock`
options to the `htlc` command since they confliced with global
options.
