engine: Support for 'AND' and 'not equal' expressions for objects with multiple tags

[klskvmr]

AND condition problem
The tag filter did not work for objects with multiple tags in the following cases:

• With search conditions for multiple tags via AND
• With the != operator

Reason:
Previously, inside the *_with_tags views (used for searching by tags), a left join was made with the tags_* views (containing the tags), and for each tag of one entity there was a separate row in the table.
Tags for one entity were in different rows and the condition with IN did not work, since it works by rows.

Example:
WHERE ( vms_with_tags.tag_name IN ('tag-1') AND vms_with_tags.tag_name IN ('tag-2') )
this condition will always be false for objects with multiple tags.

What was done to solve the problem
The tags columns types in *_with_tags views have been changed from text to arrays for support and improve tags searching with multiple conditions without increasing the complexity of the resulting SQL query.

To support filtering by tags, it was decided to use arrays. Now, to search for one or more tags, the array intersection operation (&&) is used, which allows for the correct use of several consecutive conditions with tags

The edits affected tag filters on the pages:

1. Compute -> Virtual Machines
2. Compute -> Hosts
3. Administration -> Users

Cases
All functionality is preserved, only a filter by several tags via AND is additionally supported.

	Filter search cases	Result or resulting selection
1	Filter by tag with the = operator	WORKS Objects with the searched tag and objects with its nested tags. Nested tags are taken into account! i.e. tags nested in the searched tag will also be included in the resulting selection
2	Filter by tag with the != operator	DIDN'T WORK ON OBJECTS WITH MULTIPLE TAGS (FIXED) Objects not marked with the tag from the condition. Nested tags are not taken into account!
3	Filter by tag with operators <, >, <=, >=	NOT SUPPORTED
4	Filter by several tags via OR	WORKS Objects with the searched tags and objects with tags nested in them. Nested tags are taken into account!
5	Filter by two tags via AND	DIDN'T WORK ON OBJECTS WITH MULTIPLE TAGS (FIXED) Objects containing all the searched tags or tags nested in them. Nested tags are taken into account!
6	Filter with tag and with another field	WORKS
7	Free text search	WORKS
8	Search by regular expression e.g. tag = test_ta*	WORKS
9	Search by regular expression for = e.g. tag = test_ta*	WORKS
10	Search by regular expression for != e.g. tag != test_ta*	DIDN'T WORK ON OBJECTS WITH MULTIPLE TAGS (FIXED) Objects not marked with the tag from the condition. Nested tags are not taken into account!

Changes introduced with this PR

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[klskvmr]

BEFORE FIX

Filters by tags with... (for objects with multiple tags)

• Search conditions for multiple tags via AND

• The != operator

[klskvmr]

AFTER FIX

Filters by tags with... (for objects with multiple tags)

• Search conditions for multiple tags via AND

• The != operator

[JasperB-TeamBlue]

Looks good to me, only thing that bothers me is that the tag string used as a parameter in the expressions is capital sensitive while this is not the case for expressions regarding the name of a vm. Due to this not being a previous functionality on the main branch it does not concern the scope of this patch.