Full-text search for text searching on database side

[canbax]

Currently, to make filtering in tables, we are dynamically generating database queries. (CQL for neo4j)
The method getCondition4TxtFilter makes simply brute force pattern matching.

visuall/src/app/db-service/neo4j-db.service.ts

Line 246 in 861eb3f

private getCondition4TxtFilter(isEdge: boolean, className: string, txt: string): string {

This might be problematic for big databases. To compensate, many databases support full-text search. Neo4j also supports it. https://neo4j.com/developer/kb/fulltext-search-in-neo4j/ It might be necessary to use full-text search in the future.