HPCC-9193 Clarify Page 30 Inst&RunHPCC

Fix HPCC-9193 Clarify Page 30 Inst&RunHPCC
Page 30 of Installing and Running The HPCC Platform
has a section that can easily be misunderstood.
This fix clarifies the meaning of that section.

@JamesDeFabia

Signed-off-by: g-pan <greg.panagiotatos@lexisnexis.com>