Upgrade jmake to 1.3.8-1.

commit c9e81c08db5be5074009d9414206f355d9a90017
Author: John Sirois <jsirois@twitter.com>
Date:   Mon Apr 28 10:35:56 2014 -0600

    Upgrade jmake to 1.3.8-1.

    Also fixes old twitter-commons cache dir name.

 BUILD.tools                       | 2 +-
 build-support/ivy/ivysettings.xml | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

Testing Done:
$ ./pants goal test tests/{java,scala}::
...
10:35:03 00:12           [jmake]
                         warning: bootstrap class path not set in conjunction with -source 1.6
                         Jmake version 1.3.8-1
                         Writing project database...  Done.

10:35:05 00:14         [find-missing-dependencies]
...
10:35:15 00:24   [test]
10:35:15 00:24     [junit]
10:35:15 00:24       [bootstrap-junit]
10:35:16 00:25       [run]
                     .......
                     Time: 0.165

                     OK (7 tests)

10:35:17 00:26     [specs]
               Waiting for background workers to finish.
               SUCCESS

Bugs closed: 85

Reviewed at https://rbcommons.com/s/twitter/r/282/