Add in additional Error codes and license disclaimer
Descriptions obtained from (http://src.chromium.org/svn/trunk/src/net/base/net_error_list.h)
Change formatting at @perlun's request
Merge pull request #389 from amaitland/enhancement/expand-error-enum

Expand CefErrorCode enum
Merge remote-tracking branch 'remotes/upstream/master' into cleanup/fixes-plus-api-changes