New Node Filter: Gene Annotation Regions filter (promoters etc)

*Originally reported by* **David Lawrence (Bitbucket: [davmlaw](https://bitbucket.org/davmlaw), GitHub: [davmlaw](https://github.com/davmlaw))**

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You might want to filter for promoter regions (+/- 1kb from TSS)

We have this data in gene level annotation but not sure if it's well set out to make this a quick query. Maybe we could make a separate table by uploading a GTF into the database, then turning the regions into genomic intervals.

We could then intersect as per the .bed file node.

This shouldn't be too big (at most as big as a VCF file) for all annotations and different regions. So is def worth caching the calculation in the DB.

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- Bitbucket: https://bitbucket.org/sacgf/variantgrid/issue/135