performance improvments to putClassAd with projection #4448
 - change projection from StringList to classad::References in putClassAd
 - move code for expanding the projection from call sites to putClassAd
 - use more efficient projection expansion
   - treat input projection as a list of attributes (i.e do not parse/evaluate them)
   - get internal refs only
===VersionHistory:Pending===
Merge branch 'V8_3-condor_status'