install bash completion scripts

Completion itself is not implemented.

debian/pbs.bash-completion

@@ -0,0 +1,8 @@
+# pbs bash completion
+
+# see http://tiswww.case.edu/php/chet/bash/FAQ
+# and __ltrim_colon_completions() in /usr/share/bash-completion/bash_completion
+# this modifies global var, but I found no better way
+COMP_WORDBREAKS=${COMP_WORDBREAKS//:}
+
+complete -o default -C 'pbs bashcomplete' pbs