Converts distances measured in miles and chains to kilometres, linking to chain (unit) without linking miles. This is to conform to WP:OVERLINK, which states that common units of length should not be linked. However, chains are not familiar to many readers, and therefore a link is provided.
This template is designed to mimic the function of the {{convert}} template, which is currently unable to make selective links.
If a wiki-link to chains is not required, or it is preferable to link to both miles and chains, {{convert}} can be used instead.
Note that the parameters mi, chain and km are redundant in this template, but are provided to make conversion to the {{convert}} template easier if selective linking is ever implemented.
