qt qcustomplot库demo，和高效实时绘图
#QCustomPlot 官网 https://www.qcustomplot.com/index.php/introduction
#qcustomplot_realtime 工程参考如下链接 https://blog.csdn.net/yxy244/article/details/100099876
#扩展，其他绘制频谱曲线波形方式 https://github.com/Greedysky/qt-spek https://github.com/ha7ilm/qtcsdr https://github.com/xmikos/qspectrumanalyzer https://github.com/czyt1988/sa https://github.com/blindber/MSA-Qt