popvars initial release

template parser and compiler are built and working, but not yet feature complete.

New features

straight forward "popping", a.k.a expand a.k.a interpolation or substitution: {{field}}
"popping" with "lookups" to reference another table by it's $id: {{table_name.field}} which is shorthand for the explicit index form: {{table_name@table_name.field}} which means you can reference another table using a field of the current record with a different name: e.g. {{country@`Enemy Country`.code}}
if blocks: {@ if field = "something" @}This only appears if field is equal to something{@ end if @}
for loop including "for other": {@ for other allied_country in country where team="Allies" @}This appears once for each allied country ({{allied_country}} in the `country` table, but the current country is excluded (because of the "other"){@ end for @}
cli reads csv files and outputs newline concatenated output to a single file
Documentation including README is a work in progress