position, exclusiveEnd --> start, end

In an attempt to coalesce the variant/models across several different systems, I would like to recommend using start, end instead of position, exclusiveEnd.

Source  | Coordinate system | Interval type | Position fields | Contig names
------------- | ------------- | ------------ | ----------- | ------------
ADAM|0-based|closed-open interval|position, exclusiveEnd|?
Ensembl REST client | 1-based | closed interval | start, end | "1"
VCF file|1-based|NA|position|"1" or "chr1"
GEMINI|0-based|closed-open interval|start, end|"chr1"
Google Genomics|0-based|closed-open interval|position|"1" or "chr1"
Global Alliance|0-based|?|position|"1" or "chr1"

I'll will also attempt pull requests at Google Genomics and GA4GH for position --> start, end.