Collective.documentgenerator

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- Added do_rendering field in IMergeTemplatesRowSchema schema. If selected, the subtemplate is rendered first
and the path is the value in context dict. Else the subtemplate object is the value in context dict.
[sgeulette]
- Return generation context from rendering methods to use it in tests
[sgeulette]
- Added unit testing for do_rendering feature
[odelaere, sgeulette]
- Improved validation for ConfigurablePodTemplate
[odelaere]
- Added validation to avoid generation context corruption at generation time
[odelaere]
- Manage boolean values in context variables
[sgeulette]
- Removed meta_type attribute causing error when pasting
[sgeulette]
- Do not lose filename when updating a Pod template with it's styles template
[gbastien]
- Ease override of term title of the `collective.documentgenerator.StyleTemplates` vocabulary
[gbastien]
- Define a correct portal_type description for StyleTmplate so it is displayed in the folder_factories
[gbastien]
- Modified generated filename, before it was POD template title and format, now it it build using POD template title,
context title and format
[gbastien]

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- Added parameter 'html' in display_html_as_text witch is mutually exclusive with 'field_name' to add ability to use a date field or an html formatted string with display_html_as_text.
[odelaere]
- Added parameter 'text' in display_text_as_html witch is mutually exclusive with 'field_name' to add ability to use a date field or a string with display_text_as_html.
[odelaere]
- Added parameter 'date' in display_date witch is mutually exclusive with 'field_name' to add ability to use a date field or a date object with display_date.
[odelaere]
- Added parameter `optimize_tables` to be able to use the `optimalColumnWidths`
functionnality of appy.pod.
[gbastien]

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- Update styles templates only with force param.
[sgeulette]
- Make sure `current_md5` is stored as unicode or it fails to validate when
manually validating stored data.
[gbastien]

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- Added utils method to update templates.
[sgeulette]

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- Fix widget for fields `IConfigurablePODTemplate.pod_formats` and
`IConfigurablePODTemplate.pod_portal_types` to avoid override by another
package like it is the case when using `collective.z3cform.select2`.
Use CheckBoxWidget for `IConfigurablePODTemplate.pod_portal_types` to ease
selection when displaying several elements.
[gbastien]
- Set appy renderer on view element stored in generation context.
Useful when view has been overrided in generation context getter.
[sgeulette]

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- Removed useless parameter in getDGHV method.
[sgeulette]