redo some of the transaction code, get conflicts and obsoletes partly working

now uses a bit array of to-be-installed/removed packages and uses that to
avoid needing to do either per-property searches or repeated merges. but it
really needs to have a bit array of properties too probably

checkpoint before starting on simplifying/cleaning up the existing
transaction code

 .gitignore

 *.o

 *~

 *.repo

 razor

 test-driver

 pkgs

 set

 primary.xml.gz

 filelists.xml.gz