bugfix for iedit-hide-unmatched-lines

fixed bug where iedit-hide-unmatched-lines goes
into an infinite loop if two matching lines are
exactly context-lines apart
tweak to use isearch case sensitivity

have iedit-mode use the same case sensitivity as isearch if we enter the mode from a search.
also a partial bugfix for when the search has no results
bugfix for when there are no occurrences
Add test case for iedit-hide-unmatched-lines
Merge branch 'master' of https://github.com/mbneedham/iedit
Fix the testcase for iedit-hide-unmatched-lines
Update iedit-lib.el
clean up old occurrences when calling from isearch

If iedit-mode-from-isearch is called when iedit is already active, 
it's possible to have overlays for two different patterns at the same time.
This cleans up the old occurrences before making new ones.
Merge pull request #32 from mbneedham/master

Small bugfix to clean up old occurrences when calling from isearch
Fix infinite loop problem in iedit-rect-mode
Also add a new test case
* iedit-rect.el (iedit-rectangle-mode): Fix crash emacs when region is not rectangular.
* iedit-rect.el: Fix deactivation of rectangle mode.
* iedit-rect.el: Apply upstream changes.
Merge branch 'master' into thierry-dev