Allow to pass options to javac during doc generation

[alexarchambault]

Is your feature request related to a problem? Please describe.
One sometimes needs to pass options to javac for javadoc generation, like -Xdoclint:none

Describe the solution you'd like
Scala CLI could accept directives like

//> using doc.javacOpt -Xdoclint:none

and pass those to javac during javadoc generation

Describe alternatives you've considered
Using the javacOpt directive doesn't seem to work

Additional context
Ideally, I'd like to be able to generate javadoc for the coursier/directories-jvm repository, which is a pure Java project. Trying to do so currently doesn't work, and seems to require (at least) -Xdoclint:none:

$ git rev-parse HEAD
968eb94f7c837e768e00dfc4e9971de7cc4018e1
$ scala-cli publish local .
…
Publishing io.get-coursier.util:directories-jvm:0.1.0-SNAPSHOT
Loading source file ./project.java...
Loading source file ./src/main/java/dev/dirs/BaseDirectories.java...
Loading source file ./src/main/java/dev/dirs/GetWinDirs.java...
Loading source file ./src/main/java/dev/dirs/ProjectDirectories.java...
Loading source file ./src/main/java/dev/dirs/UnsupportedOperatingSystemException.java...
Loading source file ./src/main/java/dev/dirs/UserDirectories.java...
Loading source file ./src/main/java/dev/dirs/Util.java...
Constructing Javadoc information...
Standard Doclet version 1.8.0_372
Building tree for all the packages and classes...
Generating ./.scala-build/directories-jvm_6f724d3978_c882bf022a/classes/main-doc/dev/dirs/BaseDirectories.html...
./src/main/java/dev/dirs/BaseDirectories.java:72: error: no summary or caption for table
    * </table>
      ^
…