Add argparse, _argumentNumber(), _isUrl(url)
Add _isWebsiteAlive(url), scan(url); _isUrl() typo fix
Add update(pageN), _parseHrefs(html), _writePlugins(pluginsList)
Add _main()
Add some messages to scan(url)
Remove debug messages from _isWebsiteAlive(url), add _isWebsiteAlive(url) to scan(url)
Move IOError to _main()
Add description to argParser