document the process of importing footprints from EasyEDA / LCSC

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+importing footprints from lcsc 
+
+navigate to the product detail page of the part
+
+click the EasyEDA model link under the datasheet link to get a preview
+
+click "free trial" there and the file opens in the online editor
+
+select the footprint tab
+
+File menu, File source..., Download button
+
+This saves a text file starting with ["DOCTYPE","FOOTPRINT",...; copy this 
+file into the library, start pcb-rnd, open library window: the footprint 
+should show up in the list
+
+or, just load the footprint into pcb-rnd and save it in lht format.
+
+Note that various features will import with a very tiny clearance value, 
+which will likely need to be manually adjusted.  this is a consequence of 
+how EasyEDA handles clearance differently than Ringdove.  
+
+Pay particular attention to unplated holes, where using pcb-rnd's 'hshadow' 
+in the padstack allows forcing clearance around the hole to prevent a fab 
+from mistakenly assuming you really meant a plated hole.
+