Review parameters and variables for S2I process

[rolfkleef]

Current approach:

Preparation

• Have a workspace folder
• Add files to be converted to input/
• Add variables such as org id to config/csvxml-iati.xslt

During run

• Copy "master file" to config/, so that we can include the variables stylesheet via hard-coded relative path, and the main templates as hard-coded absolute path.
• Use Ant to do the mapping of input files to intermediate and final output files, via Saxon + XSLT stylesheets (and add some other conversion tooling).

Finish

• Collect the produced IATI file.

Explore:

• Adding variables via a spreadsheet/CSV/JSON template, with more flexibility to add default values.
• Using dynamic ways to include client-specific templates? Check if it is possible to use variables as template modes.