Fixed a logic error during update of GMState.inout_x and DiGMState.in_x, and DiGMState.out_x.
Fixed a logic error during update of GMState.inout_x and DiGMState.in_x, and DiGMState.out_x.

When updating GMState.inout_1 and GMState.inout_2, we need to check if a node already
exists in the dictionary.  Otherwise, we will overwrite when the node was added to the
dictionary---this screws up backtracking.

Also, minor documentation changes.

--HG--
extra : convert_revision : svn%3A3ed01bd8-26fb-0310-9e4c-ca1a4053419f/networkx/trunk%40679

jcurbelo/networkx,NvanAdrichem/networkx,jtorrents/networkx,jni/networkx,jakevdp/networkx,sharifulgeo/networkx,farhaanbukhsh/networkx,farhaanbukhsh/networkx,chrisnatali/networkx,jakevdp/networkx,harlowja/networkx,farhaanbukhsh/networkx,beni55/networkx,debsankha/networkx,michaelpacer/networkx,chrisnatali/networkx,nathania/networkx,bzero/networkx,cmtm/networkx,ghdk/networkx,wasade/networkx,debsankha/networkx,nathania/networkx,tmilicic/networkx,dhimmel/networkx,kai5263499/networkx,dhimmel/networkx,sharifulgeo/networkx,goulu/networkx,blublud/networkx,JamesClough/networkx,RMKD/networkx,aureooms/networkx,chrisnatali/networkx,sharifulgeo/networkx,aureooms/networkx,SanketDG/networkx,kernc/networkx,harlowja/networkx,bzero/networkx,jfinkels/networkx,ionanrozenfeld/networkx,jni/networkx,ionanrozenfeld/networkx,RMKD/networkx,jni/networkx,kernc/networkx,dhimmel/networkx,nathania/networkx,ionanrozenfeld/networkx,ghdk/networkx,debsankha/networkx,jakevdp/networkx,yashu-seth/networkx,RMKD/networkx,aureooms/networkx,OrkoHunter/networkx,kai5263499/networkx,dmoliveira/networkx,dmoliveira/networkx,blublud/networkx,ghdk/networkx,Sixshaman/networkx,ltiao/networkx,kai5263499/networkx,bzero/networkx,dmoliveira/networkx,kernc/networkx,harlowja/networkx,blublud/networkx,andnovar/networkx,jtorrents/networkx