Boost.Range merge from trunk to release.
This is motivated by the need to correct the istream_range, to correct the adaptors.hpp header file, and correct the return types of various range algorithms.
Boost.Range correct missing items from merge by merging these changes manually.
This changeset is what should have happened with the prior svn merge operation.
Boost.Range documentation merge from the trunk. Corrects inconsitency with return types, Range Return Categories etc.
Merge standards-conformance fixes for Boost.Range
Move Boost.Range's join_iterator intrusive_ptr_add_ref and intrusive_ptr_release where ADL will actually find them
Merge documentation fixes.

* Use `doc/src/*.css` instead of `doc/html/*.css`.
* Remove wiki and people directories.
* Some documentation fixes.
* Left out `minimal.css` changes and boostbook changes because of clashes.
Boost.Range merge of bug fixes and documentation
Merge filesystem, range, doc from trunk.

* Inline deprecated methods in filesystem.
* Fix some links in range.
* Clean up test document a bit.
[boost][range] - merge from trunk which fixes a defect in the strided range adaptor, and contains improvements to the documentation
[range] - merge the tested changes from the trunk in preparation for the 1.46 release.
[boost][range] - Merge a fix to undo an erroneous change to iterator_range.size() that allowed it to compile for ranges that did not model the Random Access Range Concept and thereby broken the complexity guarantees.
Merge to release.
[boost][range] - merge from trunk of miscellaneous defect fixes
[boost][range] - Merge trac resolutions from the trunk. The most notable change is the alteration of the size type to be unsigned. This is a potentially breaking change.
[boost][range] merge from trunk to release
[range] merge doc fixes (r81888, r81889) from trunk
[range] merged bug fixes (r81890, refs #5603; r82071, refs #6103) from trunk
[range] Merge documentation fixes and minor refactoring of docs (refs #5160; refs #5314; refs #5440; refs #5775; refs #6212; refs #7585; refs #7843; refs #7866).
[range] merge fix for typos in comments to release branch (refs #7916)
[range] merge documentation fix from trunk (refs #7926)