Fix incorrect plot height calculation for small value ranges

fix unintended modification of input data

CLI: added option to specify legends for series `sl`

CLI: added options delimiter `d` & number of series `sn` and updated …

…option `sc` to specify series colors

Added support of legends for colored graphs

Added options to set upper & lower bound of graph

Added support for ploting ansi colored graphs

Added Dockerfile & support for plotting multiple series together

fixed incorrect y-axis start value tick & NaN first value

added support for go module, custom precision