openmpi: variants file for Linux renamed to variants.rhel6, cleanup, merlin specific stuff removed

Compiler/openmpi/files/variants.rhel6

+openmpi/1.4.3	stable		gcc/4.7.4
+
+openmpi/1.6.5	deprecated	gcc/4.9.2
+openmpi/1.6.5	stable		intel/{15.2,15.3}
+
+openmpi/1.8.2	stable		gcc/{4.7.4,4.8.3,4.8.4}
+openmpi/1.8.2	deprecated	gcc/4.9.2
+openmpi/1.8.4	stable		gcc/{4.7.4,4.8.3,4.8.4,4.9.2}
+
+openmpi/1.8.8	deprecated	gcc/5.2.0
+openmpi/1.8.8	stable		gcc/4.8.5
+
+openmpi/1.10.0	deprecated	gcc/4.9.3
+openmpi/1.10.2	stable		gcc/{4.8.5,4.9.4,5.3.0,5.4.0,6.1.0,6.2.0}
+openmpi/1.10.2	stable		intel/15.3
+openmpi/1.10.4	stable		gcc/{4.8.5,4.9.4,5.4.0,6.2.0}
+openmpi/1.10.7	stable		gcc/{4.8.5,4.9.4,5.4.0} b:cuda/8.0.44
+openmpi/1.10.7	stable		gcc/{5.5.0,6.2.0,6.3.0,6.4.0,7.2.0,7.3.0,8.2.0}
+openmpi/1.10.7	stable		intel/17.4
+
+openmpi/2.0.0	stable		gcc/6.1.0
+openmpi/2.0.0	stable		intel/16.3
+openmpi/2.0.1   stable		gcc/{4.9.4,5.4.0,6.2.0,6.3.0}
+
+openmpi/2.1.0	stable		gcc/7.1.0
+openmpi/2.1.1   stable          gcc/{6.4.0,7.2.0}
+openmpi/2.1.1   stable          intel/{17.1,17.4}
+openmpi/2.1.2	stable		gcc/7.3.0
+openmpi/2.1.2   stable          intel/17.4
+openmpi/2.1.5	stable		gcc/{4.8.5,5.5.0,6.4.0,7.3.0,8.2.0}
+
+openmpi/3.0.0   stable          gcc/{5.5.0,6.4.0,7.2.0,7.3.0}
+openmpi/3.0.0   stable          intel/17.4
+openmpi/3.0.1   stable		gcc/{5.5.0,6.4.0,7.3.0,8.1.0}
+openpmi/3.0.1   stable		intel/18.2
+openmpi/3.1.1	stable		gcc/{8.1.0,8.2.0}
+openmpi/3.1.2	stable		gcc/{7.3.0,8.2.0}
+openmpi/3.1.2	stable		intel/18.4
+openmpi/3.1.3	stable		gcc/{4.8.5,5.5.0,6.4.0,6.5.0,7.3.0,8.2.0,8.3.0}
+openmpi/3.1.4   stable          gcc/{7.4.0,8.3.0,9.1.0,9.2.0}
+
+openmpi/4.0.0	stable		gcc/{5.5,6.4,6.5,7.3,7.4,8.2,8.3}.0
+
+openmpi/4.0.1   stable		gcc/7.4.0