How To Set Env Variable in GI/CRS

Symptom:

    Sometimes we need to set env variables in CRS for Database .  For example, we need to set ORACLE_UNQNAME  for a few Databases. So each database can get its unique name from this variable. We can add other variable for different usages

Solution:

test0024!oracle (bash) /u01/app/oracle/product/12.1.0.2/dbhome_2/network/admin
testdb1% srvctl getenv database -db testdb
testdb:

test0024!oracle (bash) /u01/app/oracle/product/12.1.0.2/dbhome_2/network/admin
testdb1 % srvctl setenv database -db testdb -env "ORACLE_UNQNAME=testdb"

test0024!oracle (bash) /u01/app/oracle/product/12.1.0.2/dbhome_2/network/admin
testdb1% srvctl getenv database -db testdb
testdb:
ORACLE_UNQNAME=testdb