Fix some commenting issues

src/main/java/app/model/languages/Java.java

@@ -48,7 +48,7 @@ public class Java implements ProgrammingLanguage {
       e("\\b[A-Z]\\w+\\b",            "identifier"),
       e("\\b(" + String.join("|", keywords) + ")\\b",
                                       "keyword"),
-      e("(?://.*)|(?:\\/?\\s?\\*.*)", "comment")
+      e("(?://.*)|/\\*(?:\\n|.)*\\*/", "comment")
     );
 
   public String getName() {

src/main/java/app/model/languages/Markdown.java

@@ -21,6 +21,7 @@ public class Markdown implements ProgrammingLanguage {
 
   private static final Map<Pattern, String> pattern = 
     Map.ofEntries(
+      e("<!--(?:.|\n)*-->", "comment"),
       e("##### .*", "ssssheader"),
       e("#### .*", "sssheader"),
       e("### .*", "ssheader"),

src/main/resources/styling/languages/java.css

@@ -49,7 +49,7 @@
 }
 
 .code-area .comment {
-  -fx-fill: -light-bg-color;
+  -fx-fill: -main-comment-color;
 }
 
 .code-area .string {

src/main/resources/styling/languages/markdown.css

@@ -2,6 +2,10 @@
   -test-color: #193814
 }
 
+.code-area .comment {
+  -fx-fill: -main-comment-color;
+}
+
 .code-area .header {
   -fx-fill: -main-green-color;
   -fx-font-size: 200%;

src/main/resources/styling/themes/monokai.css

@@ -13,6 +13,7 @@
   -main-blue-color:    #66d9ef;
   -main-magenta-color: #ae81ff;
   -main-cyan-color:    #a1efe4;
+  -main-comment-color: -light-bg-color;
 
   -banana-focus-color: #fffb00;
 }

src/main/resources/styling/themes/solarized-light.css

@@ -1,8 +1,8 @@
 
 * {
-  -main-fg-color:      #002b36;
+  -main-fg-color:      #657b83;
 
-  -main-bg-color:     #eee8d5;
+  -main-bg-color:      #fdf6e3;
   -light-bg-color:     #dfd6e3;
   -dark-bg-color:      #93a1a1;
   -shadow-bg-color:    #c5bec9;
@@ -13,6 +13,7 @@
   -main-blue-color:    #268bd2;
   -main-magenta-color: #d33682;
   -main-cyan-color:    #2aa198;
+  -main-comment-color: #586e75;
 
   -banana-focus-color: #fffb00;
 }