Addition of root directory for ICL.

[SVN r67238]
Interval Container Library [Boost.Icl]. Initial merge from trunk to release branch for boost 1.46.

[SVN r67245]
Added some adapter code for posix_time::time_duration and gregorian::date_duration, so the durations can be fully used with icl::intervals.

[SVN r67348]
Minor modifications of tests.

[SVN r67404]
Adjustments for use with boost/intrusive


[SVN r67405]
Deleted generated html docs with long filenames.

[SVN r67520]
Adding quickbook html-docs that are now generated with short truncated filenames.

[SVN r67527]
Removed directories and unlinked html-files generated by older versions of quickbook.

[SVN r67610]
Fixed error in docs: element_iterators are free functions. Added example and test code.

[SVN r67939]
Removed tabs.

[SVN r67941]
Fixed tweaks in documentation.

[SVN r67957]
Merged corrections of documentation, and some adapter code for gcc-3.4.4.

[SVN r68096]
Cleaned up test_casual.cpp

[SVN r68130]
Last minute bug fix (ticket #5135) for boost 1.46.0 authorized by Rene Rivera. 

[SVN r68551]
Last minute bug fix (ticket #5135) for boost 1.46.0 authorized by Rene Rivera. 

[SVN r68552]
Merged [69071-69538] from trunk for 1.46.1. Ticket #5207, reports from John Reid, corrections on the documentation. Additions of tests. Some tests fro compiler specific issues prefixed by cmp_.


[SVN r69542]
Merged 69961-7083: (1) Fixed standard conformance issues, detected by Doug Gregor March-05. (2) Adapted implementation so boost::chrono types are usable in icl intervals and containers without customization. (3) Added tests for icl/chrono interoperability. 


[SVN r70787]
Due to Chris Jefferson's problem report on function equal_range in libxx I changed its implementation using lower_bound and upper_bound directly.

[SVN r71034]
Adjustment for lib++ associated to clang. Qualified call of this->equal_range in split_interval_set. 


[SVN r71076]
Merged changes [71328-71362] Bug fix for ticket #5482

[SVN r71364]