Test:
1. push a minor edit to github.
3. pull the edit from githug to brad's git-svn version of repository.
4. push the change to coin subversion copy using git svn dcommit.
Test:
1. push a minor edit to github.
3. pull the edit from githug to brad's git-svn version of repository.
4. push the change to coin subversion copy using git svn dcommit.

git-svn-id: https://projects.coin-or.org/svn/CppAD/trunk@3527 0e562018-b8fb-0310-a933-ecf073c7c197
Update README file.
Merge ../repo+svn
command_line_arg.cmake: put quotes around chosen value.
CMakeLists.txt: fix bug in checking cppad_max_num_threads.
Merge branch 'master' into stable/20150000