Reference std.range.chain from joiner.
Consistent use of element variable name in .map ddocs.
std.traits: clean imports

remove new private stuff
Merge pull request #2665 from 9il/traits

std.traits: clean imports
std.string: clean imports
added scope imports
added scope import
update array.d scope import
add local imports to std.uni
range/constraints.d : update imports and unites

solv unittest name conflict with std.algorithm
range/constraints.d move mixin

and update scope imports
dummyRanges
update dummyRanges
type
Merge pull request #2675 from 9il/string

std.string: clean imports
Merge pull request #2668 from quickfur/issue8087

Partial fix for issue 8087: improve std.algorithm documentation