updated help strings of commands

bin/etherdump

@@ -2,6 +2,25 @@
 
 import sys
 
+usage = """Usage:
+    etherdump CMD
+
+where CMD could be:
+    sync
+    gettext
+    gethtml
+    creatediffhtml
+    dumpcsv
+    list
+    listauthors
+    revisionscount
+    showmeta
+
+For more information on each command try:
+    etherdump CMD --help
+
+"""
+
 try:
     cmd = sys.argv[1]
     if cmd.startswith("-"):
@@ -10,13 +29,13 @@ try:
     else:
     	args = sys.argv[2:]
 except IndexError:
-    cmd = "sync"
-    args = sys.argv[1:]
-
+    print usage
+    sys.exit(0)
 try:
     # http://stackoverflow.com/questions/301134/dynamic-module-import-in-python
     cmdmod = __import__("etherdump.commands.%s" % cmd, fromlist=["etherdump.commands"])
     cmdmod.main(args)
 except ImportError, e:
-    print "Command '{0}' not available ({1})".format(cmd, e)
+    print "Error performing command '{0}'\n(python said: {1})\n".format(cmd, e)
+    print usage