Fix #18 Proposal exit position should point to correct location

[xcariba]

It should point to $0 if present

[pisv]

The patch looks good, but after some experimenting with different approaches/different snippets, it seems that an alternative fix that I have committed to the pull request branch works more consistently with regard to "tabbing" between tab stops and with regard to the "default" behavior (when there is no $0 in the snippet). For example, for the following snippet

if (${1:true|false}) {
   $2
}$0

it produces exactly the same behavior ("tabbing" and all that) as for

if (${1:true|false}) {
   $2
}

Could you try it for yourself and see if that works for you?

[xcariba]

Works for me!

[pisv]

Great! Thanks for your contribution and feedback.