Move developer guide from wiki to CONTRIBUTING.md
Use goog.dom.classlist functions

The goog.dom.classes functions have now been deprecated.
See google/closure-library@97e8a0c
Merge pull request #2370 from gingerik/classlist

Use goog.dom.classlist functions (2)
Merge pull request #2369 from probins/contribute

Move developer guide from wiki to CONTRIBUTING.md.
Merge pull request #2356 from tschaub/regenerate-info

Always regenerate info using all sources if any have changed.
Remove duplication from contributing.md
Merge pull request #2374 from probins/patch-1

Remove duplication from contributing.md
Add packages required to build the library to dependencies

This allows other packages to depend on the ol3 package and get the build tools (devDependencies are not installed when they are transitive dependencies).  The justification here is that the ol3 package becomes useful to other packages when you are able to run the build.js task.  For this task to run all of its dependencies must be available.
For jsdoc to find plugins, we need to set the cwd

This allows the `build.js` (and the exports from `generate-info.js`) to be run with a different working directory.
Make our build configs more portable by using the default src config

If a `src` config is not provided, by default, all of the library sources are included.  There is some special handling in the build task to make sure all library sources are included regardless of the path to the build config.  When someone includes a `src` config, path patterns are assumed to be relative to the current working directory (unless overriden with the `cwd` config).  So, when you use the `src` config, your config is no longer portable.
Merge pull request #2376 from tschaub/transitive

Add packages required by the build task to dependencies.
Allow for empty Point & GeometryCollection
Encode empty geometries as WKT strings
Add tests for empty & invalid WKT strings
Update mapguidesource.js

Add a method updateParams to ol.source.MapGuide.
Improve documentation for ol.Feature
Merge pull request #2360 from gingerik/wkt-lexer

WKT lexer.
Make ol.proj.METERS_PER_UNIT exportable

We need to apply the `@api` annotation to the object itself in order for it to be exportable.
Merge pull request #2390 from tschaub/unit-conversion

Make ol.proj.METERS_PER_UNIT exportable.
Merge pull request #2345 from tschaub/no-static

Remove static and other attributes from the docs.