PCB net and parameter overhaul

- merge static and parametric nets
- allow dynamic nets on the fly with `p.local_net()`
- support local-to-global position calculations with `p.xy()`
  - this also enables intra-footprint traces and zones
- add anchor type parameters to footprints

test/index.js

@@ -4,6 +4,7 @@ const yaml = require('js-yaml')
 const glob = require('glob')
 const u = require('../src/utils')
 const ergogen = require('../src/ergogen')
+require('./helpers/mock_footprints').inject(ergogen)
 
 let what = process.env.npm_config_what
 let first = process.env.npm_config_first