histogram statistics now returning a pointer
fix csv-mgrid filter.

Replace String_Op::is_number by Qt toFloat.  The problem was that
negative value where flagged as categorical.
Update of statistical computation.
fix signals for KT
Set axis limit when changing min/max
merged of dtoan thread-safe branches
Fixed qwt project from merged branches
Refactoring grid_path*

set a constant name convention for the grid_path.  Added full path in
the cpp file.
Merged fixes for cyclical dependencies

merged the branch cylical_dependency.  This commit breaks code.  With
important file being moved around.
Fix cyclical issue with current code (breaks code)

This is from the merged of the cyclic_branch

Action is now declared in the project appli:

Replace #include <actions/action.h> by #include <appli/action.h>

The input/output actions that where defined in the action project are now in the io project.

manager_repository.h/cpp have been moved from appli to utils

Replace #include <appli/manager_repository.h> by #include <utils/manager_repository.h>
Merge branch 'develop' of https://github.com/ar2tech/ar2gems into develop
Fix ordering to initialize libraries

Due to fix of cyclicity, appli is now intitialized before actions.
FIX:  actions for loading and saving grids

Previously registered with the wrong  manager
Merge remote-tracking branch 'upstream/develop' into develop

Conflicts:
	.gitignore
	ar2gems/actions/actions.vcxproj
	ar2gems/appli/appli.vcxproj
	ar2gems/appli/appli.vcxproj.filters
	ar2gems/charts/charts.vcxproj
	ar2gems/charts/charts.vcxproj.filters
	ar2gems/charts/log_data_chart.cpp
	ar2gems/filters/filters.vcxproj
	ar2gems/geostat/geostat.vcxproj
	ar2gems/grid/grid.vcxproj
	ar2gems/grid/grid.vcxproj.filters
	ar2gems/gui/gui.vcxproj
	ar2gems/gui/gui.vcxproj.filters
	ar2gems/main/main.vcxproj
	ar2gems/main/main.vcxproj.filters
	ar2gems/main_com/main_com.vcxproj
	ar2gems/main_com/main_com.vcxproj.filters
	ar2gems/math/math.vcxproj
	ar2gems/qtplugins/qtplugins.vcxproj
	ar2gems/qtplugins/qtplugins.vcxproj.filters
	ar2gems/utils/utils.vcxproj
	ar2gems/utils/utils.vcxproj.filters
	ar2gems/widget_accessor/extragui.vcxproj
Add grid/neighbors.cpp to the build