# Functions
ForceGet is fetch and parse sitemap.xml/sitemapindex.xml.
Get is fetch and parse sitemap.xml/sitemapindex.xml
If sitemap.xml or sitemapindex.xml has some problems, This function return error.
Parse create Sitemap data from text.
ParseIndex create Index data from text.
ReadSitemap is a function that reads a file and returns a Sitemap structure.
ReadSitemapIndex is a function that reads a file and returns a Index structure.
SetFetch change fetch closure.
SetInterval change Time interval to be used in Index.get.