diff --git a/LICENSE.md b/LICENSE.md
new file mode 100644
index 0000000..fdddb29
--- /dev/null
+++ b/LICENSE.md
@@ -0,0 +1,24 @@
+This is free and unencumbered software released into the public domain.
+
+Anyone is free to copy, modify, publish, use, compile, sell, or
+distribute this software, either in source code form or as a compiled
+binary, for any purpose, commercial or non-commercial, and by any
+means.
+
+In jurisdictions that recognize copyright laws, the author or authors
+of this software dedicate any and all copyright interest in the
+software to the public domain. We make this dedication for the benefit
+of the public at large and to the detriment of our heirs and
+successors. We intend this dedication to be an overt act of
+relinquishment in perpetuity of all present and future rights to this
+software under copyright law.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+For more information, please refer to <https://unlicense.org>
diff --git a/pom.xml b/pom.xml
index be9230a..cb7d756 100644
--- a/pom.xml
+++ b/pom.xml
@@ -47,13 +47,13 @@
         <maven.enforcer.plugin>3.1.0</maven.enforcer.plugin>
         <maven.install.plugin>3.0.0-M1</maven.install.plugin>
         <maven.jar.plugin>3.2.2</maven.jar.plugin>
-        <maven.pmd.plugin>3.19.0</maven.pmd.plugin>
+        <maven.pmd.plugin>3.16.0</maven.pmd.plugin>
         <maven.resources.plugin>3.2.0</maven.resources.plugin>
         <maven.site.plugin>4.0.0-M1</maven.site.plugin>
-        <maven.surfire.plugin>3.0.0-M7</maven.surfire.plugin>
+        <maven.surfire.plugin>3.0.0-M6</maven.surfire.plugin>
         <moditect.maven.plugin>1.0.0.RC2</moditect.maven.plugin>
         <native.maven.plugin>0.9.17</native.maven.plugin>
-        <spotbugs.maven.plugin>4.7.3.0</spotbugs.maven.plugin>
+        <spotbugs.maven.plugin>4.7.2.0</spotbugs.maven.plugin>
         
         <!-- other properties -->
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
@@ -219,6 +219,7 @@
                     </dependency>
                 </dependencies>
                 <configuration>
+                    <sourceEncoding>${project.build.sourceEncoding}</sourceEncoding>
                     <minimumTokens>100</minimumTokens>
                     <targetJdk>${java.version}</targetJdk>
                     <rulesets>