Allow breakpoint setting / deleting from vim

Added some common vim configuratio that can be sourced when working on
the project:

 - Add all the generated tags files
 - Configure and source the valgrind plugin
 - Configure and source the breakpoints plugin

The set breakpoints work with makefile.include, so that:
     make gdbtest
will load them. Vim will display a little icon next on lines
that have breakpoints configured