add bash markup

contrib/alfred.md

@@ -1,11 +1,11 @@
 # Start Master Server
-```
+```bash
 alfred -i wlan0 -b none -m
 # -b batmanif to be used on router
 ```
 
 # Save Data
-```
+```bash
 # Note that 0 - 63 are reserved (please send an e-mail to the
 # authors if you want to register a datatype), and can not be used
 # on the commandline. Information must be periodically written
@@ -15,7 +15,7 @@ cat r.xml | gzip | alfred -s 64
 ```
 
 # Load Data
-```
+```bash
 # 00:16:ea:c3:b8:26 is the mac of the sender
 alfred-json -z -f string -r 64 | python -c 'import sys,json;print(json.load(sys.stdin)["00:16:ea:c3:b8:26"])'
 ```