1. Move common test infrastructure into test_util.
2. system_test now only contains powells function.
3. Add bundle_adjustment_test.
Instead of a single function which computes everything,
there is now a test for each solver configuration which
uses the reference solution computed by the fixture.
Change-Id: I16a9a9a83a845a7aaf28762bcecf1a8ff5aee805
Since Ceres is moving to using GitHub for issues, and the Google
Code URL in the current copyright header will soon become invalid,
update all the headers.
Change-Id: I1fce70375d1bcf098591f07b4d8f01a5c1e0789c
Sameer Agarwal