* Added support for configuring google analytics
* Adding a configuration parameter 'ga_key' under DXR section
  will publish google analytics snippet in all templates
  this will require rebuilding the templates
* Renamed google analytics configuration key as 'google_analytics_key'
  from existing 'ga_key'
* Documented google_analytics_key in configuration.rst
  Fixes some issues with the last commit
* Added test to verify non-existance of google analytics snippet
* Added tests to check google analytics snippet
* remove the import of 'run'
* Fix test names and doc strings
* Add a test file required to build
Line no in search results act as links
fixed indentation
added fix to results.html
added missing closing anchor
Merge Google Analytics support. Fix bug 1045204. Close #332.
Fix indentation. Remove extra <td>.
Link line number in search results. Fix bug 1063462. Close #344.
Fix crash in dxr/build.py when source tree is empty.
Merge master into es to solve some conflicts before I completely forget what the right answers were.

Pick up Google Analytics support, linked line numbers, and a few other things.
Move clang-specific tests inside the clang plugin.

I want to be able to see what's a core test and what's a test for a specific plug, now that there's a difference. The triggering event is that I'm about to add some more clang integrations tests so I can then make them pass, and I don't want to make the tangle worse to do it.
Standardize names of executables in tests to "code" so we don't need to add more git ignores.
Quit updating submodules; we don't use them anymore.