test cases on Ivanov 2020 and ExB demonstrations

testcases/ExB_shear_demo/2D_Z_pinch/GS2_method/fort_01.90

testcases/ExB_shear_demo/2D_Z_pinch/background_Er/fort_01.90

testcases/ExB_shear_demo/2D_Z_pinch/fort_00.90

testcases/ExB_shear_demo/GS2_method/fast_analysis.m

testcases/ExB_shear_demo/GS2_method/fort_00.90

testcases/ExB_shear_demo/background_Er/fast_analysis.m

testcases/ExB_shear_demo/background_Er/fort.90

testcases/ExB_shear_demo/background_Er/fort_00.90

testcases/Ivanov_2020/README

testcases/Ivanov_2020/fort_00.90

testcases/Ivanov_2020/fort_01.90

testcases/Ivanov_2020/fort_02.90

testcases/Ivanov_2020/fort_03.90

testcases/zpinch_example/fort_00.90