6900: *** HtmlRenderer.WebDom

Separate HtmlRender.WebDom to another
6901: UserMapUtil
6901.1: SpecSetter
6902: refactor
6904: HtmlRenderer.Composers

1. Move HtmlRenderer.WebDom to HtmlRenderer.Composers
2. Move EventCore to   HtmlRenderer.Composers
6905: refactor
6906: refactor
6907: ContentManagers

move to HtmlRenderer.Composers
Merge branch 'v1.7dev' into v1.7
6908: BoxSpec' s CloneAllStyles, InheritStyles

change to static method
6909 :update BoxModelBuilder
6911: refactor
6914: refactor
6915
Merge branch 'v1.7dev' into v1.7
Merge branch 'v1.7'