CSPACE-6135: Implement services-readonly field handling.

Conflicts:

	cspi-schema/src/main/java/org/collectionspace/chain/csp/schema/Field.java
	cspi-schema/src/main/java/org/collectionspace/chain/csp/schema/Repeat.java
	tomcat-main/src/main/resources/defaults/base-collectionobject.xml
PAHMA-924: Add services-readonly='true' to computedCrate.
PAHMA-924: Fix a merge conflict.
PAHMA-1010: Set default max connections per host to 20, and warn when limit is reached.
PAHMA-1010: Minor refactoring, and delete closed connections when the max has been reached.
Merge branch 'ucb-deploy_3.3' into botgarden_3.3