Add conda virtual environment

[ms3056]

Please consider adding the Python Environment name to the front of the string like:

(python3.7) Blah Blah>Blah Blah>

Thanks!

[DemirTonchev]

I was able to add conda env like this:

---------------- show conda venv 

local function get_py_env(env_var)
    env = clink.get_env(env_var)
    if env then
        return env
    end

    return false
end

local function get_conda_env_filter()
    local env = get_py_env("CONDA_DEFAULT_ENV")

    if env then
        env = addTextWithColor("[", env.."] ", ansiFgClrWhite  , ansiBgClrBlack)
        clink.prompt.value = string.gsub(clink.prompt.value, plc_prompt_lambSymbol, env..plc_prompt_lambSymbol)
    end

    return false
end

-- Register this addon with Clink
clink.prompt.register_filter(get_conda_env_filter, 100)
clink.prompt.register_filter(addAddonSegment, 55)