[Colocation] Make colocated tables default for SQL databases

[rkarthik007]

Jira Link: [DB-414](https://yugabyte.atlassian.net/browse/DB-414)
SQL databases often have many tables, most of these are often very small. It would be good to start with colocated tables by default, and proceed to splitting only those tables that are observed to be growing fast. Below is a list of tasks in order to accomplish this.

Status	Feature	GitHub Issue	YugabyteDB Version
✅	Design doc for colocated tables
✅	Support ALTER TABLE for colocated tables	#4293	v2.2
⬜️	Optimize joins in colocated tables	#4515	v2.2, v2.3
⬜️	Support TABLEGROUP syntax for colocated tables in YSQL		v2.3
⬜️	Online index rebuild for colocated tables		v2.3
⬜️	Support multiple colocation groups in one database	#4525	v2.3
⬜️	Support backup and restore for colocated tables	#4517	v2.3
⬜️	xCluster replication support in colocated tables	#4516	v2.3
⬜️	Manually pull out fast growing tables from colocation group	#4396	Consider for v2.3
⬜️	Route query to colocated tablet leader’s YSQL server	#4514
⬜️	Automatically pull out fast growing tables from colocation group	#4396

[frozenspider]

This is now outdated, tracking issue moved to #11665