Update the new version to CRAN and add JHL as a contributor

DESCRIPTION

@@ -1,13 +1,15 @@
 Package: SLSEdesign
 Title: Optimal Regression Design under the Second-Order Least Squares Estimator
-Version: 0.0.2
+Version: 0.0.3
 Authors@R: 
     c(person(given = "Chi-Kuang", family = "Yeh",
              role = c("aut", "cre"),
              email = "[email protected]",
              comment = c(ORCID = "0000-0001-7057-2096")),
       person(given = "Julie", family = "Zhou",
-             role = c("aut", "ctb")))
+             role = c("aut", "ctb")),
+      person(given = "Jason", family = "Hou-Liu",
+             role = c("ctb")))
 Description: With given inputs that include number of points, discrete design space, a measure of skewness, models and parameter value, this package calculates the objective value, optimal designs and plot the equivalence theory under A- and D-optimal criteria under the second-order Least squares estimator. This package is based on the paper "Properties of optimal regression designs under the second-order least squares estimator" by Chi-Kuang Yeh and Julie Zhou (2021) <doi:10.1007/s00362-018-01076-6>. 
 URL: https://github.com/chikuang/SLSEdesign
 BugReports: https://github.com/chikuang/SLSEdesign/issues