chore(release): 3.1.0 [skip ci]

# [3.1.0](v3.0.0...v3.1.0) (2022-01-30)

### Features

* Support JPG and PDF as additional output formats ([5e67b16](5e67b16))

chore(release): 3.0.0 [skip ci]

# [3.0.0](v2.0.0...v3.0.0) (2022-01-30)

### Bug Fixes

* Upgrade dependencies ([7ab6b54](7ab6b54))

### BREAKING CHANGES

* * The minimum version of Node.js is 12 instead of 8. The `commander` dependency requires at least that version.
* The command line parameter to set the image height is `-H, --height`. The `h` conflicted with the `-h, --help` option.

chore: Drop support of Node.js 6

BREAKING CHANGE: Minimum version of Node.js has to be 8 from now on, because of the node-canvas dependency.

chore: Drop builds with Node.js 6

fix: Lock canvas to 1.x

Before upgrading tp the new interface oin the 2.x branch.

docs: Refine the home page URL

chore: Dropped support of Node.js 4

Some NPM dependencies dropped support of Node.js 4. It is easier to drop it
too, that looking for workarounds to get the testing build running, or claim
the support without actually testing it.

Add testing with Node.js 10.

BREAKING CHANGE: Dropped support of Node.js 4

fix: Upgrade semantic release and other dependencies

Cache npm cache and not local node modules in Travis.

chore(tests): Divide the tests for imports to no imports, cyrrent dir…

…ectory and process directory paths

Merge pull request #10 from prantlf/greenkeeper/nomnoml-0.2.0

Update nomnoml to the latest version 🚀