Moving toward PDF metadata insertion

Added a command-line switch that gets the PHP script to spit out a metadata file suitable for use with pdftk.
Added a "%.meta" target in the makefile
Made the PHP script more compartmentalized and functional
Told .gitignore to ignore Vim swap files
Refactoring and metadata

* Makefile now treats SVG output as precious
* PHP script broken up into more functions to pave the way for layouts using external files
* "presets" directory created, to hold constant definitions for dimensions and the like
Some more cleanup