(PDB-830) Regexp array operator is too greedy

This changes the regular expression, and moves the delimiter lookahead guard
so it is only introduced when a wildcard/style search is introduced.

Signed-off-by: Ken Barber <ken@bob.sh>
Merge pull request #1055 from kbarber/ticket/master/pdb-830-regexp-array-operator-is-too-greedy

(PDB-830) Regexp array operator is too greedy
(maint) Fix regexp array operator test failures for PostgreSQL

PostgreSQL deals with lookaheads differently to HSQLDB, this work-around
switches a .* to an or'd regexp that matches in functionality but still
retains the expected look ahead behaviour. This is all to ensure we still
pin regexp lookups to within the delimiters.

I've also fixed that case where users might provide a number and expect
that to be matched exactly.

Signed-off-by: Ken Barber <ken@bob.sh>
(maint) Fix reference to greedy regexp operator

The regexp operator had a bug that made it greedy, this example in fact-paths
docs shows this bug and is now incorrect. This patch fixes the curl query.

Signed-off-by: Ken Barber <ken@bob.sh>
Merge pull request #1057 from kbarber/maint/master/broken-regexp-test

(maint) Fix regexp array operator test failures for PostgreSQL