Make connection.tables method return tables from all schemas. Issue #18

Task 13289
Add missing docs

Task 13289
Address yard warnings

Task 13289
Get rid of unused fk_options variable

Task 13289
Make specs pass with postgresql 9.3

Task 13297
Make #tables method return public tables without schema prefix

Task 13289
Merge TMXCredit/pg_power#42 and TMXCredit/pg_power#43 v1.6.4 'origin/13289_tables' and 'origin/13297_postgresql9.3'

Task 13289
Task 13297
Task 13293
Task 13299

* origin/13289_tables:
  Make #tables method return public tables without schema prefix
  Get rid of unused fk_options variable
  Address yard warnings
  Add missing docs
  Make connection.tables method return tables from all schemas. Issue #18

* origin/13297_postgresql9.3:
  Make specs pass with postgresql 9.3