Add the ability to specify the Flash Entry Point in the case of 'Run Target After Program Load'.

This will be useful in (at least) 2 scenarios:

1) Where .hex files are used for programming. The PC is set to 0x0 in this case and so the loaded program will not run. Please see related question.

2) Where an application is not located at the usual flash entry point. For example, when the application is developed in parallel with a bootloader but the bootloader is not present or available. In this case the application is not located at the hard coded flash entry point. Running the application without a bootloader would assist collaboration between bootloader and applications teams.