Adding documentation for typical usages of OpenFAST #2288

Job	Run time
build-all-debug-single	3m 12s
build-postlib-release	10m 33s
build-drivers-release	8m 10s
build-all-debug	6m 12s
build-test-uadriver-debug	2m 14s
rtest-modules-debug	6m 40s
rtest-module-drivers	4m 32s
build-openfast-release	3m 21s
build-interfaces-release	3m 44s
build-fastfarm-release	14m 47s
rtest-OF-5MW_Land_AeroMap	1m 13s
rtest-OF-5MW_Land_BD_DLL_WTurb	2m 18s
rtest-OF	7m 5s
rtest-OF-5MW_OC3Mnpl_DLL_WTurb_WavesIrr	1m 37s
rtest-OF-5MW_OC3Trpd_DLL_WSt_WavesReg	4m 48s
rtest-OF-5MW_OC4Jckt_DLL_WTurb_WavesIrr_MGrowth	1m 18s
rtest-OF-5MW_OC4Semi_WSt_WavesWN	1m 52s
rtest-OF-linearization	2m 29s
rtest-OF-simulink	10m 11s
rtest-interfaces	4m 45s
rtest-FF	1m 53s
	1h 42m 54s

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