TMDM-7455 : added junit testcase
Prevent NPE in buggy situation where field to index doesn't have a database equivalent.
TMDM-7455 Cannot search FK Record when having FK contains other FK
- If reference field type is not String, ignore the condition
TMDM-7455: "Cannot search FK Record when having FK contains other FK"

Revert for alternative in implementation.
TMDM-7455: "Cannot search FK Record when having FK contains other FK"

Alternative for implementation of fix: reuses isAssignable(...) method to check if value is assignable for field when using contains.
TMDM-7499: "Improve always false condition handling"

Initial commit for constant conditions and modification in normalize code.
TMDM-7499: "Improve always false condition handling"

Fix regressions on type checking (xsi:type) and security cleaning.
Merge branch 'bugfix/TMDM-7455' into feature/5.6/TMDM-7499

Conflicts:
	org.talend.mdm.core/src/com/amalto/core/query/user/UserQueryBuilder.java
Update unit test (use "or" iso. "and" in contains conditions).
TMDM-7349: implementation of remove and re-add portlets and portal column switching logic
https://jira.talendforge.org/browse/TMDM-7349
remove redundant code
https://jira.talendforge.org/browse/TMDM-7349
TMDM-7349: add Domain Config section and some cosmetic improvements
TMDM-7349: fix a potential defact--mssing sending colum config to ActionPanel after all portlets initilized from scratch(no config info from cookies)
TMDM-7452 tMDMInput search with FK field throws exception
- Return list 'as it is' if it's not PersistentList
https://jira.talendforge.org/browse/TMDM-7452
TMDM-7467: "Match simulation inconsistencies when using a blocking key"

In memory storage: add support for compare operations on built-in block key.
XML serialization: includes built-in block key if caller asks for metadata dump in XML.
Unit tests: improve test data (include a common built-in block key).
# This is a combination of 3 commits.
# The first commit's message is:
TMDM-7455 : added junit testcase

# This is the 2nd commit message:

TMDM-7455 Cannot search FK Record when having FK contains other FK
- If reference field type is not String, ignore the condition

# This is the 3rd commit message:

TMDM-7455: "Cannot search FK Record when having FK contains other FK"

Revert for alternative in implementation.
Integrates changes for TMDM-7455 within TMDM-7499 changes.
TMDM-7499: Improve constant condition support

Introduces new expression for constant condition (that can be either always true or false).
New unit test for feature.