updated docs in node_wrapper.py to reflect use of mkdtemp when base_directory=None
updated docs in node_wrapper.py to reflect use of mkdtemp when base_directory=None

git-svn-id: 24f545668198cdd163a527378499f2123e59bf9f@478 ead46cd0-7350-4e37-8683-fc4c6f79bf00

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