Add SVG output format support

Added

• SVG output format support

Removed

• Dot output format support

Header file include dependency visualisation

• Issue #8: Make this work even in projects that have no discernible structure

Update deprecated dependencies and add new functionality

[0.4.0] - 2020-04-12

Added

• Issue #8 - Add ability to visualise includes of header_files

v0.1.3

Fixed

• String encoding forced to UTF-8 when invalid encoding detected

v0.1.2

Add Rubygems API key