Appy 0.8.5

This is the last release of series 0.8. It is a bugfix release, also including minor improvements, mainly at the gen and px levels. This is the last 'gen' version where ZPTs (Zope Page Templates) will work. They will be replaced with PXs (appy.px=PythonXml) in the next Appy version.

[pod,px] 'loop' variable, available in the pox/px context, allows to know if we are managing an even or odd elem via loop.<elem>.odd and loop.<elem>.even.

[gen]
- Added the posssibility to create a custom widget that displays an icon for generating a doc from a pod field, but with an additional param allowing to customize the pod context.
- Some actions were triggered via icons. That was not explicit enough for basic users. So now, every action is triggerd by a button that displays an icon+a text.
- In the process of migrating from ZPT (Zope Page Templates) to appy.px (Python Xml).
- On Page instances, one may now define a method for conditionnally showing the 'edit' button on 'view' layout.
- An app may now, on its Config class, define a method getHomeObject that must return an object that will be the home object for a given (class of) user(s). This object's menu will appear when the user is consulting a page with no tied menu (like a search for example).
- Moved Appy fields into appy/fields together with their PX.
- Added a validator for String fields, for validating Belgian NISS numbers.
- Replaced, in PXs, function 'img' by function 'url', that returns the URL of an external resource to be included in the XHTML, like an image, a Javascript file or a CSS file.
- Created param config.groupsForGlobalRoles that disables by default creation of a group for every global role.
- On a appy class it is now possible to define a static method 'generateUid' that generates a UID for every instance of this class, instead of using the standard Appy way to produce such UIDs.
- Changed the way to customize the Config in an app.

[px]
- PX is now thread-safe.
- Added the possibility to have several PX actions in the same XHTML tag. If several PX actions are defined, they are evaluated in this order: var, for, if.
- Added tag 'var2', similar to 'var', but that is executed after tags 'for' and 'if'.
- Managed special HTML attributes like 'checked' and 'selected'.
- Better error reporting when encountering a parsing error in a PX.
- Added boolean param 'unicode' that defines if PX result must be unicode or an encoded str.

[shared]
- dav: improved Resource.soap: better handling of HTTP header SOAPAction.
- dav: Upgraded dav.py to use httplib.HTTPConnection instead of httplib.HTTP.
- dav.Resource: allow to retrieve the result encoded or not in utf8.