Update toolbox.js
Update toolbox.js

Changed style attribute to categorystyle.
mark-friedman/blockly,google/blockly,rachel-fenichel/blockly,nickmain/blockly,rachel-fenichel/blockly,picklesrus/blockly,mark-friedman/blockly,nickmain/blockly,picklesrus/blockly,joshlory/blockly,google/blockly,google/blockly,nickmain/blockly,google/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,google/blockly,picklesrus/blockly,joshlory/blockly,mark-friedman/blockly,nickmain/blockly,mark-friedman/blockly,nickmain/blockly,google/blockly,mark-friedman/blockly,joshlory/blockly,google/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,mark-friedman/blockly,nickmain/blockly