Update data-tar-ball target.

Exclude stray .bak files (not an issue right now).
Add HLA+MP directories (after all ;-) ).
Add ASK13 glider.
Some 'tabification'.

Makefile.am

@@ -40,6 +40,7 @@ data-tar:
 	tar \
 	--exclude=CVS \
 	--exclude='*~' \
+	--exclude='*.bak' \
 	--exclude='*.tex' \
 	--exclude='*.xcf' \
 	--exclude='*/c172/Instruments.high' \
@@ -60,6 +61,7 @@ data-tar:
 		data/Aircraft/UIUC \
 		data/Aircraft/777-200 \
 		data/Aircraft/A6M2 \
+		data/Aircraft/ASK13 \
 		data/Aircraft/b1900d \
 		data/Aircraft/bo105 \
 		data/Aircraft/c172p \
@@ -83,6 +85,7 @@ data-tar:
 		data/Environment \
 		data/Fonts \
 		data/gui \
+		data/HLA \
 		data/Huds \
 		data/Input \
 		data/joysticks.xml \
@@ -92,6 +95,7 @@ data-tar:
 		data/materials.xml \
 		data/mice.xml \
 		data/Models \
+		data/MP \
 		data/N* \
 		data/options.xml \
 		data/preferences.xml \