change solvers, utilities, etc. to use while (..) time-looping idiom

- this (now deprecated) idiom:
      for (runTime++; !runTime.end(); runTime++) { ... }
  has a few problems:
    * stop-on-next-write will be off-by-one (ie, doesn't work)
    * function objects are not executed on exit with runTime.end()
  Fixing these problems is not really possible.

- this idiom
      while (runTime.run())
      {
          runTime++;
          ...
      }
  works without the above problems.