Configurable checkers

[ArchangelSDY]

Background

Currently some checkers hardcode thresholds / parameters. Users might want different values.

Goals

• Provide a way to customize checker parameters.

Design

• Provide command line argument to specify a config file.
• Support a global config file under HOME directory.
• Provide an easy-to-use API for checker writers.

[yanshudan]

Hi I'm working on this task, could you please include me in the project and assign this to me ? @ArchangelSDY