Initial draft of CRAM specification as a TeX document.
Fixed some \texttt segments.

Fixed a few table headings and adjusted widths.
Moved the images to img and the cram.tex to the root directory.
Math-ify the formulae.
Added lists and various enumerations instead of manual 1., 2. lines.
Tidy up of title page and changed version number in initial paragraph.
Merge pull request #22 from jkbonfield/master

CRAM specification