Refactoring of PropertyEditTool's counter into a more generic function

Introduces a generic counter factory in wb.utilities.buildPendingCounter. Allows to generate
counters like the one in the site-links table which will display fixed quantity number plus,
optionally, a pending quantity.

* removed the following messages since they've been replaced with more generic ones:
  - 'wikibase-propertyedittool-counter'
  - 'wikibase-propertyedittool-counter-pending'
  - 'wikibase-propertyedittool-counter-pending-pendingsubpart'
  The new messages are similar but parameters have slightly changed. ccc documentation for new
  messages has been added and is similar to ccc of above.

- patch set 2: added dependencies to tipsy and language modules required for the counter
- patch set 3: qqq cleanup and tooltip rtl fix

Change-Id: Ibf5ebbd1189ba496fa829ba496f055ed1d89e099
Merge "Refactoring of PropertyEditTool's counter into a more generic function"