Minor updates

• Added file_pos function for vcflib progress bar
• Added #pragma once
• Updated htslib to latest

Minor fixes and updates

• Updated htslib and replaced deprecated function
• static library build
• Makefile fixes
• added guix.scm
• added make test
• updated README

point release for debian packaging

Shout out to @mr-c

initial tagged release

v1.0.0

Create LICENSE