Use of ServiceLoader for ease of adding new languages

[ZenHarbinger]

I have gone through for my own purposes and added some interfaces and classes which can be loaded using the Java ServiceLoader class.

I have added this functionality to LanguageSupportFactory for finding supported languages.
A new interface LanguageSupportRegistration is added with methods:

String getLanguage();
String getLanguageSupportType();

The ServiceLoader will then find all implemented classes in LanguageSupportFactory and add them on the fly.
META-INF.services/org.fife.rsta.ac.LanguageSupportRegistration keeps the record of all implementing classes similar to the above TokenMakerRegistration.

Similarly I have added org.fife.ui.rsyntaxtextarea.TokenMakerRegistration in the RSyntaxTextArea project.
From here each language then implements a class that derives from this interface.
The interface provides 3 methods.

String getLanguage();
String getTokenMaker();
FoldParser getFoldParser();

which are used in DefaultTokenMakerFactory. Instead of manually specifying every language, the ServiceLoader class can find the files from the META-INF.services/org.fife.ui.rsyntaxtextarea.TokenMakerRegistration file which keeps a record of all implementing classes. Using maven (not sure about gradle) there are plugins which will automatically fill in this file when building.

[bobbylight]

This would be slick, but I'm old and crotchety and want RSTA to stay buildable/runnable with JDK 5. For this reason I won't be merging this pull request until I decide to get with the times.

I'm creating a milestone for things like this just so I don't lose track of them.

[ZenHarbinger]

I was able to set the compiler settings in the pom.xml file for maven to use java 1.5 and it worked.
<maven.compiler.source>1.5</maven.compiler.source>
<maven.compiler.target>1.5</maven.compiler.target>

[bobbylight]

Unfortunately the ServiceLoader class was added in 1.6.

[ZenHarbinger]

Close in reference to using: #35
With less intermediary files (pom.xml) and no changes to existing gradle build process.