Test start equals end in tabix, and make sure end overlaps work

[cmdcolin]

This tests a special situation of a VCF where the start and end parameters are set to be the same e.g.

tabix -0 -s 1 -b 2 -e 2 -f out.bed.gz

A file is attached as a test

This is assumed to be a 1bp wide feature.

It also adds some more curlies because it looks better to me :)

[codecov]

Codecov Report

Merging #94 into master will increase coverage by 0.08%.
The diff coverage is 89.47%.

@@            Coverage Diff             @@
##           master      #94      +/-   ##
==========================================
+ Coverage   90.71%   90.79%   +0.08%     
==========================================
  Files           7        7              
  Lines         549      554       +5     
  Branches      150      150              
==========================================
+ Hits          498      503       +5     
  Misses         51       51              

Impacted Files	Coverage Δ
src/tabixIndexedFile.ts	91.62% <89.47%> (+0.24%)	⬆️

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[garrettjstevens]

This tests a special situation of a VCF where...

Did you mean BED instead of VCF (since that's what the test file is)?

[cmdcolin]

Ya it was a BED file not a VCF..mistyped

[cmdcolin]

And, strictly speaking, it was not a BED file, it is a custom file where you just have a refName:position, in what I think implies 1bp wide feature, so I implemented it this way

[garrettjstevens]

Got it, makes sense