Exonviz

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+ Add option to specify variant shape
+ Set default variant shape to pin

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+ Set the default gap size to zero
+ Add documentation to readthedocs

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+ Automate release process

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+ Increase gap size after phase-0 exon to improve visuals

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+ Fix a bug when --firstexon is smaller than 1
+ Show a warning when variants are dropped

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+ Show detailed errors from mutalyzer
+ Use mutalyzer_hgvs_parser to check user input
+ Include the smallest scale a transcript can be drawn at in the error message
when the scale is too small
+ Fix a bug where the legend is truncated if it is wider than the transcript,
but smaller than the page
+ Add check for invalid values for `--width`, `--height`, `--scale` and `--gap`
when drawing
+ Scale estimated legend size with the specified `--height`
+ Add explicit `--scale` option
+ Fix a bug breaking `--firstexon` and `--lastexon` option