test: classifier: RFvariableImportanceTest: Clarify error checking assertion code.
test: classifier: RFvariableImportanceTest: Clarify error checking assertion code.

ThomasWalter/vigra,mmuellner/vigra,dstoe/vigra,mmuellner/vigra,timoMa/vigra,funkey/vigra,ThomasWalter/vigra,capturePointer/vigra,dagophil/vigra,cha007/vigra,funkey/vigra,capturePointer/vigra,timoMa/vigra,ThomasWalter/vigra,funkey/vigra,dagophil/vigra,capturePointer/vigra,capturePointer/vigra,xiwei-zhang/vigra,ThomasWalter/vigra,cha007/vigra,cha007/vigra,ThomasWalter/vigra,cha007/vigra,timoMa/vigra,kod3r/vigra,dstoe/vigra,timoMa/vigra,ThomasWalter/vigra,dstoe/vigra,capturePointer/vigra,funkey/vigra,kod3r/vigra,xiwei-zhang/vigra,kod3r/vigra,timoMa/vigra,xiwei-zhang/vigra,timoMa/vigra,xiwei-zhang/vigra,mmuellner/vigra,dagophil/vigra,mmuellner/vigra,dagophil/vigra,mmuellner/vigra,capturePointer/vigra,ThomasWalter/vigra,timoMa/vigra,xiwei-zhang/vigra,dstoe/vigra,xiwei-zhang/vigra,kod3r/vigra,dagophil/vigra,capturePointer/vigra,cha007/vigra,dstoe/vigra,xiwei-zhang/vigra,kod3r/vigra,kod3r/vigra,kod3r/vigra,dstoe/vigra,cha007/vigra,dagophil/vigra,mmuellner/vigra,cha007/vigra,dstoe/vigra,funkey/vigra,funkey/vigra,mmuellner/vigra,dagophil/vigra,funkey/vigra