add zsh and bash completion scripts

etc/bash-completion/scrot

@@ -0,0 +1,24 @@
+#!/bin/bash
+
+_scrot_autocomp() {
+	local -a _scrot_opt_list
+	IFS=$'\n' _scrot_opt_list=( $(scrot --list-options=tsv) ) 2>/dev/null
+	local _scrot_opts=""
+	for ln in "${_scrot_opt_list[@]}"; do
+		local -a tokens
+		IFS=$'\t' tokens=( ${ln} )
+
+		local sopt="${tokens[0]}"
+		local lopt="${tokens[1]}"
+		# TODO: better support for flags that accept argument
+		# local argtype=${tokens[2]%%:*}
+		# local argdesc=${tokens[2]#*:}
+		# local desc="[${tokens[3]}]"
+		_scrot_opts+="--${lopt} "
+		if [[ "$sopt" = [[:alnum:]]* ]]; then
+			_scrot_opts+="-${sopt} "
+		fi
+	done
+	printf "%s" "${_scrot_opts% }"
+}
+complete -W "$(_scrot_autocomp)" scrot

etc/zsh-completion/_scrot

@@ -0,0 +1,27 @@
+#compdef _scrot scrot
+
+function _scrot() {
+    local -a args
+    local list=$($~words[1] --list-options=tsv) 2>/dev/null
+    for ln in ${(f)list}; do
+        IFS=$'\t' local tokens=( ${=ln} )
+
+        local sopt="${tokens[1]}"
+        local lopt="${tokens[2]}"
+        local argtype=${tokens[3]%%:*}
+        local argdesc=${tokens[3]#*:}
+        local desc="[${tokens[4]}]"
+
+        case "$argtype" in
+            R) desc+=":$argdesc" ;; # Required
+            O) sopt+="+"; lopt+="=" ;; # Optional
+            N) ;; # None
+        esac
+
+        if [[ "${sopt}" = [[:alnum:]]* ]]; then
+            args+=( "-${sopt}${desc}" )
+        fi
+        args+=( "--${lopt}${desc}" )
+    done
+    _arguments "${args[@]}"
+}