This constitutes a large change in how we will parse different data
formats going forward (for the plugins that support it)
This is working off @henrypfhu's changes.
This will basically make the root directory a place for storing the
major telegraf interfaces, which will make telegraf's godoc looks quite
a bit nicer. And make it easier for contributors to lookup the few data
types that they actually care about.
closes#564
Cameron Sparr
Gabriel Levine
Reginaldo Sousa
Andrea Sosso
Jack Zampolin
Thibault Cohen