Task #10811: added some initial tests on inserting tasks and claims and checking claim/task conflicts

Task #10784: Renamed claim status "claimed" (ID 0) to "tentative" and claim status "allocated" (ID 1) to "claimed" in both Python code and  database creation/allocation scripts. Successfully verified that all unit tests that originally passed still pass, and that those that originally didn't pass, don't give new errors.

Task #10810 - Postgres database is now created and populated for tests. Added some simple tests that directly operate on the database directly or through RADataBase.

Task #9893: RA DB sql: clean cherry pick merge on .sql files and .py generators from SAS-RA_DRAGNET-Task9939 branch. This concerns commits r36414,r36422,r36449,r36450,r36464,r36503,r36504,r36505,r36507,r36559,r36560

Task #9939: RA DB sql: remove earlier added DRAGNET max fill percentage. Rename CEP4 max fill percentage to a ratio

Task #8570: renamed dir from ResourceAssignmentDatabase to ResourceAssignmentDatabase.from_branch_to_prevent_svn_conflict to prevent svn EvilTwin merge conflict. Rename back on trunk.