Adding new quickstart versions of setchplenv.*

These versions are identical to the ones in util except that
they also set...

CHPL_TASKS  = fifo (to avoid the default of qthreads)
CHPL_GMP    = none (to avoid a speculative build of gmp in the future)
CHPL_REGEXP = none (to avoid a speculative build of regexp in the future)
Updated README to reflect new "Quick Start" workflow and refer to PERFORMANCE

The main change here is to swap steps 2 and 3.  The reason we did the
make before the environment previously was so that (a) because we
could (and it validated that the make worked without any specific
settings) and (b) one could say "You only need to do steps 3 onward
once the initial build has been done" (though the insertion of the
make check step arguably broke this as well).

Added two new steps at the end of the Quick Start list, one that tells
how to build the preferred configuration; a second that points to the
PERFORMANCE file in hopes of avoiding the dreaded --fast question.
Updating test release script to match quick start instructions

To make testReleaseHelp track the changes I just made to the
top-level README and quick start instructions, it now

a) sets the environment before issuing the make command
b) sets the environment using the util/quickstart/setchplenv.* script
   rather than the util/setchplenv.* script

Further TODOs:

* rewrite this from csh to bash so that we're testing the shell we
  consider most common now

* make this also test the non-quickstart case to make sure it works
  too.
Adding the util/quickstart/ directory to those to be included in the release
Minor wording changes to README based on hildeth feedback
Merge pull request #275 from bradcray/quickstart

Implement new "Quick Start" approach

This commit does three main things:

1) Makes a copy of the top-level util/setchplenv.* scripts in a
   util/quickstart/ subdirectory and modifies them to set...

     CHPL_TASKS = fifo
     CHPL_REGEXP = none
     CHPL_GMP = none

   (the final two are not strictly necessary as this is where they
   default anyway, but with other changes that I'm working on, they
   will become necessary quickly; and don't hurt in the meantime)

   It also updates the gen_release script to include this new
   util/quickstart subdirectory.


2) Updates the top-level README to:

   - have new users use these quickstart/setchplenv.* scripts

   - give instructions for switching to the "preferred" setchplenv.*
     scripts

   - point to the PERFORMANCE file (in hopes of reducing the frequency
     of people not using the --fast flag)

   (also does some minor wordsmithing)


3) Updates the release testing script to better match the README
   instructions by:

   - using the quickstart script

   - setting the environment before making (now required for
     quickstart)


Some related TODOs are to:

* rewrite the release testing script to use a bash environment rather
  than csh since that's the use case we care most about now

* extend the release testing script to test both the quickstart and
  preferred environments

* make all nightly testing use the release tarball rather than the
  repository