Minor method renaming and commenting
Fix sorting handling on post type pages
Redo year start and close date functions

* Rename fct_year_started to fct_year_started_text
* Rename fct_year_closed to fct_year_closed_text
* New fct_get_year_started_text
* New fct_get_year_closed_text
* Redo fct_get_year_started to return true date value
* Redo fct_get_year_closed to return true date value
* Minor List Table fixes
Add year close date GMT

* Rename fct_get_current_time to fct_current_time
* Add List Table column content comments
* Fix some docblocks
Output year start/close date in abbreviation
Enable filtering accounts by ledger id
Fix account filter meta query vars
Introduce record date meta to hold physical record date

Record date meta as opposed to record post date will hold the date
the record references to in real life. The record post date will
be holding the date the record was inserted in Fiscaat.

* Remove some legacy record value_type or amount_type references
* List Table: set numerical post ordering to initial DESC
* Some additional comment fixing