bug_actiongroup.php: Allow setting an empty version.

diff --git a/bug_actiongroup.php b/bug_actiongroup.php
index a378242..7c0ab32 100644
--- a/bug_actiongroup.php
+++ b/bug_actiongroup.php
@@ -249,7 +249,7 @@ foreach( $f_bug_arr as $t_bug_id ) {
 		$t_project_id = bug_get_field( $t_bug_id, 'project_id' );
 
 		if ( access_has_bug_level( config_get( 'update_bug_threshold' ), $t_bug_id ) ) {
-			if ( version_get_id( $f_fixed_in_version, $t_project_id ) !== false ) {
+			if ( $f_fixed_in_version === '' || version_get_id( $f_fixed_in_version, $t_project_id ) !== false ) {
 				/** @todo we need to issue a helper_call_custom_function( 'issue_update_validate', array( $t_bug_id, $t_bug_data, $f_bugnote_text ) ); */
 				bug_set_field( $t_bug_id, 'fixed_in_version', $f_fixed_in_version );
 				helper_call_custom_function( 'issue_update_notify', array( $t_bug_id ) );
@@ -266,7 +266,7 @@ foreach( $f_bug_arr as $t_bug_id ) {
 		$t_project_id = bug_get_field( $t_bug_id, 'project_id' );
 
 		if ( access_has_bug_level( config_get( 'roadmap_update_threshold' ), $t_bug_id ) ) {
-			if ( version_get_id( $f_target_version, $t_project_id ) !== false ) {
+			if ( $f_target_version === '' || version_get_id( $f_target_version, $t_project_id ) !== false ) {
 				/** @todo we need to issue a helper_call_custom_function( 'issue_update_validate', array( $t_bug_id, $t_bug_data, $f_bugnote_text ) ); */
 				bug_set_field( $t_bug_id, 'target_version', $f_target_version );
 				helper_call_custom_function( 'issue_update_notify', array( $t_bug_id ) );