Prevented test for defer attribute to match file name in src attribute; Added corresponding unit-test

The current test for defer attribute match the following:
`<script src="path/containing/defer-keyword.js"></script>`
I added a space character as a prefix to avoid matching a file path unexpectedly.
Support multiple targets in useminPrepare
Fix directory structure in example
Add support for configurable staging option.
Merge pull request #194 from dharFr/defer-false-positive

Prevented test for defer attribute to match file name in src attribute;
Merge pull request #206 from sorich87/usemin-prepare-multiple-targets

Support multiple targets in useminPrepare
Grammar and Spelling fixes
Merge pull request #211 from tekay/patch-1

Fix directory structure in example
Merge pull request #215 from Gamaroff/patch-1

Grammar and Spelling fixes
Merge pull request #212 from alimfeld/master

Add support for configurable staging option.
fix / "staging" option not passed to ConfigWriter
Merge pull request #217 from rafalgalka/fix-staging-option

fix / "staging" option not passed to ConfigWriter
Fix typo
Merge pull request #229 from rubenv/patch-1

Fix typo
Removed ref to v2.0 as it has been merged
fix / include block search path in block destination
(corresponds to #184 and #186)
Merge pull request #226 from rafalgalka/fix-block-search-path

fix / include block search path in block destination
2.0.1
Revert back #226. Should fix at least #204, #476, #473 and #472
Update README.md

Fixed 'scrips' typo