updated default square size to mirror A4 calibration chart at 2.5x2.5cm
updated default square size to mirror A4 calibration chart at 2.5x2.5cm

HalfdanJ/ofxCv,cran-io/ofxCv,xionluhnis/ofxCv,tgfrerer/ofxCv,SpecularStudio/ofxCv,arturoc/ofxCv,wenbo001/ofxCv,tgfrerer/ofxCv,DHaylock/ofxCv,wenbo001/ofxCv,danoli3/ofxCv,cran-io/ofxCv,wenbo001/ofxCv,SpecularStudio/ofxCv,DHaylock/ofxCv,tgfrerer/ofxCv,DHaylock/ofxCv,danoli3/ofxCv,arturoc/ofxCv,SpecularStudio/ofxCv,danoli3/ofxCv,anthonykylai/test1,anthonykylai/test1,cran-io/ofxCv,arturoc/ofxCv,HalfdanJ/ofxCv,xionluhnis/ofxCv,anthonykylai/test1,HalfdanJ/ofxCv,xionluhnis/ofxCv