Usage of MJR's density of states utils. (Acknowledgements due to
RS and CJP)

Step 1
------

./bands < out.log

OR

./bands.msi < castep.cst          # if MSI output file

Creates / overwrites band.dat with list of band energies and
k-point weights. "out.log" must contain just one list of
band energies, or confusion will result, but apart from
that it is a standard CASTEP log file. (I.e. run CASTEP with
NITER=1 and ISUBROT=1, or just cut off the end of a suitable
log file.)

Step 2
------

./DoS

(respond sensibly to questions)

Creates / overwrites DosOut which contains energy values and
density, suitable for gnuplot or similar. Also reports the
number of electrons in input & output. Ensure they are the
same!