Merge pull request #436 from aspiers/master

README.md: fix 'filter!' typo
Removed outdated section about filesystem handling

Filesystem adapters are now handled by the Listen gem.

Therefore I propose to delete this entire section, since this is all handled transparently. I have created a Wiki page and moved the content there. https://github.com/guard/guard/wiki/Efficient-Filesystem-Handling
Merge pull request #438 from tilsammans/patch-1

Removed outdated section about filesystem handling [ci skip]
Fixing broken link for adding proper readline support
Merge pull request #439 from theroux/master

Fixes broken link in Readme [ci skip]
Merge pull request #440 from aspiers/master

warn about nasty bugs in listen [ci skip]