Psi4 can now be configured with CMAKE.  Users familiar with configure scripts will
probably prefer to use the configure.cmake script, which will call CMake with the
appropriate options (run

configure.cmake -h

to see which options are available and how it should be used).  CMake can also be 
invoked directly, as described below.  Builds must be performed in a separate
build directory, and can be customized through command line arguments or by
passing definitions to cmake.  As an example, we'll consider building the code
from $PSI4/obj.  The basic cmake invocation would be

    cmake ..

To set the installation directory and C++ compiler to use, we can do either

    cmake .. -D PREFIX=/path/to/psi -D CXX=g++

or
    # on BASH-like shells
    export PREFIX="/path/to/psi" 
    export CXX=g++
    # on CSH-like shells
    setenv PREFIX "/path/to/psi"
    setenv CXX=g++

    cmake ..

These can be mixed in any order, with -D commands taking precedence.  Psi4
currently recognizes the following options:-

CXX              The C++ compiler. N.B. This must be set as an environmental variable, not a -D flag. (string)
                 default:whichever compiler is first detected by cmake

CXXFLAGS         Extra C++ compiler flags to be used in compilation (string)
                 default:""

F77SYMBOL        The Fortran compiler name mangling convention, used for linking external Fortran libraries,
                 such as BLAS. Values are lcu (lower case with traling underscore), lc (lower case), 
                 ucu (upper case with trailing underscore), uc (upper case). If omitted CMake will detect it
                 automatically if a Fortran compiler is present, if not it will use lcu. (string)

LDFLAGS          Extra flags to be used in linking (string)
                 default:""

LAPACK           Linker flags to use for Lapack (and BLAS), instead of detecting system library (string)
                 default:""

MAX_AM_ERI       The maximum angular momentum to allow for integrals (1=p,2=d,3=f, etc.).  First and second
                 derivatives are supported up to MAX_AM_ERI-1 and MAX_AM_ERI-2, respectively. (int)

PREFIX           The installation directory for psi4 (string)
                 default:/usr/local/psi4

PYTHON           Full path to python interpreter to use. If omitted Python will be detected. There should be
                 a corresponding python-config script in this location for Psi to work, i.e. Python development
                 version. (string)
                 default:""

USE_SYSTEM_BOOST Whether to use system boost, if detected. False forces Psi to build its own Boost. (boolean)
                 default:true


It is strongly recommended that you delete the CMakeCache.txt in the object
directory when changing build parameters, to prevent previous cached values
being used instead of those being passed to cmake.
