Added migration of --jvm-jdk-paths to --jvm-distributions-paths

Followon to https://rbcommons.com/s/twitter/r/2677/

Testing Done:
CI running at https://travis-ci.org/pantsbuild/pants/builds/79001324

Tested locally against the square java repo.

Bugs closed: 2149

Reviewed at https://rbcommons.com/s/twitter/r/2781/

migrations/options/src/python/migrate_config.py

@@ -20,6 +20,7 @@
   ('DEFAULT', 'bootstrap_buildfiles'): ('goals', 'bootstrap_buildfiles'),
 
   ('jvm', 'missing_deps_target_whitelist'): ('compile.jvm-dep-check', 'missing_deps_whitelist'),
+  ('jvm', 'jdk_paths'): ('jvm-distributions', 'paths'),
   ('compile.java', 'missing_deps'): ('compile.jvm-dep-check', 'missing_deps'),
   ('compile.java', 'missing_direct_deps'): ('compile.jvm-dep-check', 'missing_direct_deps'),
   ('compile.java', 'missing_deps_whitelist'): ('compile.jvm-dep-check', 'missing_deps_whitelist'),