Move constants into config using get_configuration_template

[jayvdb]

plugins/constants.py should be removed, replaced with config variables defined using get_configuration_template

see http://errbot.io/en/latest/user_guide/plugin_development/configuration.html

[jayvdb]

Note that I explored this problem a little bit for #413

I found that this meant that the plugin could only be configured using !config , and didnt have the ability to load settings from a global config.

It is critical that corobo starts up using preset values from a config file.

As a result I did the following as a bit of a workaround:

    def get_configuration_template(self):
        config = {
           'CROSSLINK_GITHUB_TOKEN': '',
           'CROSSLINK_GITLAB_TOKEN': '',
           'CROSSLINK_OPENHUB_TOKEN': '',
        }

        for key in config:
            if hasattr(self.bot_config, key):
                config[key] = getattr(self.bot_config, key)

        return config

    def _get_config(self, key):
        if self.config and key in self.config:
            return self.config[key]
        return getattr(self.bot_config, key, None)

We could put something similar into a super class for all our plugins, but it feels like this might be better as an improvement in errbot upstream.

[jayvdb]

plugins/constants.py contains

• MAX_MSG_LEN & MAX_LINES - this was effectively done in configuration: Use default configurations #588 , and it doesnt hurt to leave these constants in plugins/constants.py as they can now be overriden

• GH_ORG_NAME & GL_ORG_NAME - will be removed in LabHub: Use activate and configuration templates #577

• API_DOCS & USER_DOCS - used by plugins/searchdocs.py

So after #577 is merged, this issue is only about searchdocs plugin.