Add a button to flip between flyouts and toolboxes.
Add a button to flip between flyouts and toolboxes.

twodee/blockly,hkoi/blockly,picklesrus/blockly,trinketapp/blockly,groklearning/blockly,google/blockly,jano42/blockly,InspectorWidget/blockly,drigz/blockly,drigz/blockly,google/blockly,LLK/scratch-blocks,RealTimeWeb/blockly,trodi/blockly,griffpatch/scratch-blocks,carlosperate/blockly,griffpatch/scratch-blocks,LLK/scratch-blocks,joshlory/blockly,mark-friedman/blockly,groklearning/blockly,twodee/blockly,daarond/blockly,daarond/blockly,sclements/scratch-blocks,mark-friedman/blockly,google/blockly,TechplexEngineer/blockly,daarond/blockly,jano42/blockly,aravart/speech-blocks,picklesrus/blockly,trodi/blockly,TechplexEngineer/blockly,dhalupa/blockly,mark-friedman/blockly,lzairdking/blockly,carlosperate/blockly,trinketapp/blockly,jstnhuang/blockly,sclements/scratch-blocks,gengshenghong/scratch-blocks,groklearning/blockly,InspectorWidget/blockly,lzairdking/blockly,lzairdking/blockly,nickmain/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,markocelan/blockly-minecraft,groklearning/blockly,google/blockly-devtools,griffpatch/scratch-blocks,google/blockly-devtools,griffpatch/scratch-blocks,drigz/blockly,trinketapp/blockly,carlosperate/blockly,markocelan/blockly-minecraft,mark-friedman/blockly,jano42/blockly,trinketapp/blockly,sclements/scratch-blocks,twodee/blockly,google/blockly,rachel-fenichel/blockly,twodee/blockly,rachel-fenichel/blockly,InspectorWidget/blockly,trodi/blockly,google/blockly,carlosperate/blockly,twodee/blockly,google/blockly,dhalupa/blockly,LLK/scratch-blocks,sclements/scratch-blocks,nickmain/blockly,hkoi/blockly,mark-friedman/blockly,rachel-fenichel/blockly,jstnhuang/blockly,picklesrus/blockly,rachel-fenichel/blockly,nickmain/blockly,nickmain/blockly,griffpatch/scratch-blocks,gengshenghong/scratch-blocks,rachel-fenichel/blockly,twodee/blockly,markocelan/blockly-minecraft,gengshenghong/scratch-blocks,RealTimeWeb/blockly,mark-friedman/blockly,joshlory/blockly,jano42/blockly,nickmain/blockly,gengshenghong/scratch-blocks,LLK/scratch-blocks,lzairdking/blockly,google/blockly,nickmain/blockly,jstnhuang/blockly,hkoi/blockly,jstnhuang/blockly,joshlory/blockly,gengshenghong/scratch-blocks,aravart/speech-blocks,markocelan/blockly-minecraft,dhalupa/blockly,trodi/blockly,sclements/scratch-blocks,LLK/scratch-blocks,RealTimeWeb/blockly