tar: Fix GNU tar help output parsing regex, fixes #15

Author: scop

completions/tar

@@ -105,7 +105,7 @@ __gnu_tar_parse_help()
         # or more options separated by ', ' separator string.  We are matching
         # like this then:  ^<spaces>(<separator>?<option>)+<whatever>$
         if [[ "$line" =~ \
-            ^[[:blank:]]{1,10}(((,[[:blank:]])?(--?([\]\[a-zA-Z0-9?-=]+))(,[[:space:]])?)+).*$ ]]; then
+            ^[[:blank:]]{1,10}(((,[[:blank:]])?(--?([\]\[a-zA-Z0-9?=-]+))(,[[:space:]])?)+).*$ ]]; then
 
             line=${BASH_REMATCH[1]}
             str="${line//,/ }"