sch2fig/: rename "layer" to "record", and use "layer" for layers in recordings

Clearing up massively confusing naming.

sch2fig/Makefile

@@ -13,7 +13,7 @@
 NAME = sch2fig
 OBJS = main.o sch-parse.o sch-render.o lib-parse.o lib-render.o \
        file.o \
-       style.o fig.o layer.o cairo.o gfx.o dwg.o text.o misc.o
+       style.o fig.o record.o cairo.o gfx.o dwg.o text.o misc.o
 
 CFLAGS = -g -O -Wall -Wextra -Wno-unused-parameter -Wshadow \
 	 -Wmissing-prototypes -Wmissing-declarations \