Add test Makefile for short clips.

Signed-off-by: Stefan Westerfeld <stefan@space.twc.de>

src/short.mk

+all: short-60 short-60-mp3 \
+  short-50 short-50-mp3 \
+  short-40 short-40-mp3 \
+  short-30 short-30-mp3 \
+  short-20 short-20-mp3 \
+  short-10 short-10-mp3
+
+short-60:
+	AWM_FILE=t-short-60 AWM_CLIP=60 fer-test.sh 10 "" > tmp-short-60
+	mv tmp-short-60 short-60
+
+short-60-mp3:
+	AWM_FILE=t-short-60-mp3 AWM_CLIP=60 fer-test.sh 10 "" mp3 128 > tmp-short-60-mp3
+	mv tmp-short-60-mp3 short-60-mp3
+
+short-50:
+	AWM_FILE=t-short-50 AWM_CLIP=50 fer-test.sh 10 "" > tmp-short-50
+	mv tmp-short-50 short-50
+
+short-50-mp3:
+	AWM_FILE=t-short-50-mp3 AWM_CLIP=50 fer-test.sh 10 "" mp3 128 > tmp-short-50-mp3
+	mv tmp-short-50-mp3 short-50-mp3
+
+short-40:
+	AWM_FILE=t-short-40 AWM_CLIP=40 fer-test.sh 10 "" > tmp-short-40
+	mv tmp-short-40 short-40
+
+short-40-mp3:
+	AWM_FILE=t-short-40-mp3 AWM_CLIP=40 fer-test.sh 10 "" mp3 128 > tmp-short-40-mp3
+	mv tmp-short-40-mp3 short-40-mp3
+
+short-30:
+	AWM_FILE=t-short-30 AWM_CLIP=30 fer-test.sh 10 "" > tmp-short-30
+	mv tmp-short-30 short-30
+
+short-30-mp3:
+	AWM_FILE=t-short-30-mp3 AWM_CLIP=30 fer-test.sh 10 "" mp3 128 > tmp-short-30-mp3
+	mv tmp-short-30-mp3 short-30-mp3
+
+short-20:
+	AWM_FILE=t-short-20 AWM_CLIP=20 fer-test.sh 10 "" > tmp-short-20
+	mv tmp-short-20 short-20
+
+short-20-mp3:
+	AWM_FILE=t-short-20-mp3 AWM_CLIP=20 fer-test.sh 10 "" mp3 128 > tmp-short-20-mp3
+	mv tmp-short-20-mp3 short-20-mp3
+
+short-10:
+	AWM_FILE=t-short-10 AWM_CLIP=10 fer-test.sh 10 "" > tmp-short-10
+	mv tmp-short-10 short-10
+
+short-10-mp3:
+	AWM_FILE=t-short-10-mp3 AWM_CLIP=10 fer-test.sh 10 "" mp3 128 > tmp-short-10-mp3
+	mv tmp-short-10-mp3 short-10-mp3