Update copyright year #67

Job	Run time
docs_examples_latex_pdf (cvode)	1m 35s
docs_examples_sphinx_pdf (arkode)	3m 22s
docs_examples_latex_pdf (cvodes)	1m 24s
docs_install_guide_pdf	1m 35s
docs_examples_latex_pdf (ida)	1m 25s
docs_package_pdf (arkode)	3m 35s
docs_examples_latex_pdf (idas)	1m 31s
docs_package_pdf (cvode)	3m 19s
docs_examples_latex_pdf (kinsol)	1m 19s
docs_package_pdf (cvodes)	3m 38s
docs_package_pdf (ida)	2m 56s
docs_package_pdf (idas)	2m 21s
docs_package_pdf (kinsol)	1m 55s
	29m 55s

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