docs update - form module

Signed-off-by: Dirk Jesse <office@highresolution.info>
Several improvements

Added main element to normalize core module
Added ym-contain() mixin: usage for columns and grids module

Signed-off-by: Dirk Jesse <office@highresolution.info>
updated jQuery plugins

SyncHeight - v1.5
AccessibleTabs - v1.9.7

Signed-off-by: Dirk Jesse <office@highresolution.info>