Fix #1396 : Allow objects inheriting from list or tuple

A SimpleListAdapter doesn't accept objects inheriting form list or
tuple, because it checks directly the type.

Here, in place of testing the type of the object, we use isinstance.

Also provide a testcase
uix:TextInput introduce `input_type` property to choose the type of
Keyboard to request, could be extended later to enable input mask using
same property
core: introduce clipboard provider for android, fix long touch bubble on
android
uix:TextInput fix weakref issues with cut copy paste dialog
clipboard: add only the correct provider depending on the platform
uix:TextInput introduce new properties to handle input type of keyboard
and add selctin handles.
uix:TextInput add middle handle and move choosing the type of input
to platform... py4a. kivy-ios part is TODO.
uix:TextInput add missing image and minor fixes for selection handles
Doc: include parameter:input_type docstring for method:request_keyboard
Update __init__.py
Added zsh and cygwin support for kivyenv.sh
kivyenv.sh: fixed error and minor cleanup
Parent widget of ListItemButton and ListItemLabel can now be an object of any class that subclasses CompositeListItem
Allow install on 32bit MacOSX 

Tested with the showcase and some example apps, as no test suite is available. Looks like it works on my old i386 macbook...
Removed SD card requirement from doc
doc: revisions to atlas.py (2)
doc: revisions to base.py
Merge pull request #1601 from inclement/android_doc

Removed SD card requirement from doc
Merge pull request #1599 from alanjds/patch-1

Allow install on 32bit MacOSX
Merge pull request #1597 from ydm/master

ListItemButton and ListItemLabel require CompositeListItem only