Add 'experimental-webgl' to ol.webgl.CONTEXT_IDS_ (IE11 support)

see: http://msdn.microsoft.com/en-us/library/ie/ff975238(v=vs.85).aspx
Remove social-links.js script from examples and doc
Remove webgl-experimental from ol.webgl.CONTEXT_IDS_
Merge pull request #1050 from fredj/social-links.js

Remove social-links.js script from examples and doc
Merge pull request #1049 from fredj/webgl_ie11

Add 'experimental-webgl' to ol.webgl.CONTEXT_IDS_ (IE11 support)
Use typedef in source code for SourceOptions
Differentiating doc from apidoc

This renames the doc task to apidoc.  The apidoc delegates to jsdoc3 currently.  We will have additional documentation that is not built by jsdoc3.  It makes sense to reserve the more general 'doc' name for building all documentation (not just apidoc).
Merge pull request #1054 from tschaub/apidoc

Differentiating doc from apidoc.
Merge pull request #1047 from twpayne/remove-load-events

Remove source load events
Merge pull request #1053 from elemoine/sourceoptions

Use typedef in source code for SourceOptions
Replace source ready flag with loading/ready/error enum