Remove ol-simple.js build

We've proven that we can, but that doesn't mean we should be building with `SIMPLE_OPTIMIZATIONS`.
Generate a ol-debug.js script useful for debugging

Instead of running everything through the Compiler just to remove whitespace, we provide a build that is a simple concatenation of all scripts in dependency order.  This build (ol-debug.js) should never be used in production (the same applies to the old ol-whitespace.js build).  Instead, the intention is that it be used to aid in debugging during development.
Two ways to run the hosted examples: compiled and raw

When viewing the hosted examples, people can load the compiled version of the library or load each script individually.
Removing the build-all target

The ol-all.json and ol.json build configurations differ only in their use of the manage_closure_dependencies Compiler option.  I don't think there is value in running both (there are plenty of other compiler options that we don't exercise in this same way).
Merge pull request #2404 from tschaub/builds

Two ways to use the library: advanced compilation (prod) or raw/concatenated (dev).