Allow rows and headers to be altered before export a webform

Problem/Motivation

Sometimes is required to include data regarding the user that sent the webform. The information is in the database but there is no an easy way to do that using webforms. At least is no possible without rewriting 25% of the webform module code.

The proposed solution will not fix the problem by itself, but at least will allow developers to create custom modules to get the information they are intending to get.

Proposed resolution

We have 2 hooks to alter headers and rows individually (one per component), there would be great if we could have two more hooks to alter the whole header and the whole row once it was processed.

Remaining tasks

• Provide the new two hooks.
• Document them.

User interface changes

None.

API changes

Two new hooks:

• hook_webform_csv_headers_alter(&$header, $submission);
• hook_webform_csv_row_alter(&$row, $submission);

Data model changes

None.