make readme easier to read

Some things I "freely" adjusted to make it sound better.

Only line 93: "BING search results always meet, like many others" I have no clue what you mean with this sentence and therefore cannot rewrite it. It's no good English though ;)
added some comments to bingSearchRouter
Merge branch 'master' of https://github.com/senlin/smart-search into senlin-master

Conflicts:
	README.txt
make readme easier to read