Check PostgreSQL version number as number in the makefile

Not entirely happy about the solution but I like the uniform tests.
Tests on COLLATE only run on PG versions supporting it
Make the version number arith without using bc

Not as available as I thought.

Can't use the 0 prefix to make the 3rd number optional as $(()) parses is as
octal, so only use the first 2 numbers.

Also fixed collate test: not available on PG 9.0.
Ignore AFTER triggers sorting after z_repack_trigger

They are not a problem, and they fore after the BEFORE trigger anyway.

To be checked against more PostgreSQL versions.
Install plpgsql on test databases 8.3 and 8.4

Required by triggers tests
Ignore regression tests output
Parse tablespace/where in parse_indexdef

Makes injecting the target tablespace much easier and fixes interaction
between tablespace and WITH/WHERE clauses.

Added tests to check the correct indexes definition.
Merge branch 'funky-version-check'

Conflicts:
	bin/expected/repack.out
	bin/sql/repack.sql