Disable text selection setting if we get a NPE when using clipboard.

Workaround for Issue 1746.
A Samsung bug leaves devices unable to use the clipboard. AnkiDroid
will crash while using the clipboard on those devices (i.e., every time
the reviewer opens). Here, we disable the text selection setting so
the clipboard isn't used and AnkiDroid can continue to review cards.
Merge pull request #52 from hssm/disable-clipboard

Disable text selection setting if we get a NPE when using clipboard.