BUG: Use VISTA_Path only if it is set
BUG: Use VISTA_Path only if it is set

Add conditional logic to not use the VISTA_Path until it has been set up
by the developer.  Also address the Make command not found.

Change-Id: Ibd28ba0d3cd80293b83491b34ebd35607dfdaec1

josephsnyder/VistA,jasonli2000/VistA,mdgeek/VistA-FHIR-CWF,OSEHRA-Sandbox/VistA,jasonli2000/VistA,josephsnyder/VistA,josephsnyder/VistA,mdgeek/VistA-FHIR-CWF,mdgeek/VistA-FHIR-CWF,apexdatasolutions/VistA,mdgeek/VistA-FHIR-CWF,apexdatasolutions/VistA,josephsnyder/VistA,timmvt/VistA_tt,OSEHRA-Sandbox/VistA,timmvt/VistA_tt,OSEHRA-Sandbox/VistA,OSEHRA-Sandbox/VistA,OSEHRA/VistA,timmvt/VistA_tt,josephsnyder/VistA,OSEHRA/VistA,mdgeek/VistA-FHIR-CWF,OSEHRA/VistA,shabiel/VistA,OSEHRA/VistA,timmvt/VistA_tt,josephsnyder/VistA,shabiel/VistA,shabiel/VistA,shabiel/VistA,apexdatasolutions/VistA,OSEHRA/VistA,timmvt/VistA_tt,OSEHRA/VistA,apexdatasolutions/VistA,mdgeek/VistA-FHIR-CWF,OSEHRA-Sandbox/VistA,shabiel/VistA,apexdatasolutions/VistA,shabiel/VistA,jasonli2000/VistA,OSEHRA-Sandbox/VistA,jasonli2000/VistA