Quick hack to support #785 (<nickname> before the engine command)

[kaorahi]

You can write <foo> ./leelaz -g -w network.gz in the menu Settings > Engine for example. Then foo is used as the label in the engine menu and ./leelaz -g -w network.gz is used as the actual engine command.

This is just a quick hack to support #785. It is not a good way. But it seems to be desired strongly by some people (ref.).

[NTUST-MITLAB]

As long as the nickname doesn't have a < character inside... just a fair warning, pattern matcher is sometimes dangerous...