Alternative break button scheme

[psiinon]

I've committed some changes to the way the break buttons work.
These changes are optional but are the new default - you have to change the configuration via the 'Options/Breakpoints'  to go back to the previous scheme.
I havnt changed the help yet - I'd like feedback as to whether these changes are worth including, need other changes etc

The changes are:

• One Break button instead of 2 separate 'Break on Requests' and 'Break on Responses' buttons
• The 'Continue' button unsets the single Break button
• If the single Break button is manually unset while a request or response is being held then the 'Step' button now acts in the same way as 'Continue' ie it leaves 'step' mode

Please have a play (via the trunk or the latest weekly release) and let me know what you think.

If most people like the changes to the Continue and Step buttons then we could also apply them to the '2 button' mode.

Cheers,

Simon