Monkey patch traits._Undefined to add __len__ method for traitsUI list_editor to work.
Monkey patch traits._Undefined to add __len__ method for traitsUI list_editor to work.

git-svn-id: 24f545668198cdd163a527378499f2123e59bf9f@1375 ead46cd0-7350-4e37-8683-fc4c6f79bf00

fprados/nipype,grlee77/nipype,sgiavasis/nipype,Leoniela/nipype,sgiavasis/nipype,iglpdc/nipype,Leoniela/nipype,rameshvs/nipype,arokem/nipype,fprados/nipype,pearsonlab/nipype,christianbrodbeck/nipype,mick-d/nipype,wanderine/nipype,carlohamalainen/nipype,Leoniela/nipype,dgellis90/nipype,gerddie/nipype,dgellis90/nipype,iglpdc/nipype,mick-d/nipype_source,mick-d/nipype,JohnGriffiths/nipype,sgiavasis/nipype,FCP-INDI/nipype,FredLoney/nipype,gerddie/nipype,glatard/nipype,rameshvs/nipype,arokem/nipype,mick-d/nipype_source,dmordom/nipype,glatard/nipype,dmordom/nipype,grlee77/nipype,mick-d/nipype,dgellis90/nipype,grlee77/nipype,carolFrohlich/nipype,blakedewey/nipype,carlohamalainen/nipype,mick-d/nipype,blakedewey/nipype,carolFrohlich/nipype,pearsonlab/nipype,wanderine/nipype,mick-d/nipype_source,arokem/nipype,JohnGriffiths/nipype,grlee77/nipype,gerddie/nipype,satra/NiPypeold,dmordom/nipype,blakedewey/nipype,carolFrohlich/nipype,carolFrohlich/nipype,iglpdc/nipype,glatard/nipype,rameshvs/nipype,sgiavasis/nipype,pearsonlab/nipype,dgellis90/nipype,JohnGriffiths/nipype,FCP-INDI/nipype,wanderine/nipype,carlohamalainen/nipype,iglpdc/nipype,rameshvs/nipype,wanderine/nipype,blakedewey/nipype,FredLoney/nipype,FCP-INDI/nipype,pearsonlab/nipype,arokem/nipype,FCP-INDI/nipype,glatard/nipype,FredLoney/nipype,fprados/nipype,JohnGriffiths/nipype,gerddie/nipype,christianbrodbeck/nipype,satra/NiPypeold