Add new shiny app for non linear models : gompertz

v2019.9.0

new version of package

Add new shiny app for non linear models

new shiny app 04c and 04d

Add new shiny app for non linear models

v2019.7.0

update version

Tutorial sdd2_03a

add new tutorial: sdd2_03a

Tutorial sdd2_02a

tutorial 02a : new tutorial

Tutorial sdd2_02b : new tutorial

tutorial 02b new tutorial

Tutorial 01b : minor correction

v2019.3.0

tutorial 01b minor correction

Tutorial sdd2_01b

v2019.2.0

edition second tutorial

Tutorial sdd2_01a

v2019.1.0

first realese 2019.1.0