R*tree implementation based on boost::variant

[SVN r70531]
removed unneeded files

[SVN r70533]
other version of split algorithm + a lot of minor changes

[SVN r70607]
overlap error patch + minor changes

[SVN r70627]
rtree Box template parameter removed

[SVN r70689]
namespaces hierarchy changed

[SVN r70701]
tagstags are now in the index namespace


[SVN r70702]
choose_next_node algorithm changed

[SVN r70746]
reinsert implemented

[SVN r70964]
reinsertions disabled + minor changes

[SVN r71544]
new creation algorithm added

[SVN r71634]
rtree::find parameters changed

[SVN r71640]
operator| moved to namespace index

[SVN r71642]
insert algorithm divided to tag dispatched parts

[SVN r71658]
searching time tests related code added

[SVN r71664]
remove algorithm added + some other changes

[SVN r71726]
quadratic split algorithm added, error in linear split corrected

[SVN r71755]
quadratic split error corrected

[SVN r71763]
corrected: gcc compile errors, wrong assert in remove; + minor changes

[SVN r71764]
cleanup

[SVN r71775]