include the 'Roboto' font in extra/fonts

CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,

OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

INCLUDED FONTS

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Please note that PlotFX includes third party default fonts in extra/fonts. These

are copyright of their respective authors and are licensed under different

conditions. Please see the LICENSE files in the extra/fonts directory for more

information.