Update tests/nginx-tests/nginx-tests/lib/Test/Nginx.pm

set prefix when start nginx
add sent_cookie variable
Merge pull request #162 from skoo87/sent_cookie

added $sent_cookie_XXX variable
add .gitignore
Merge pull request #163 from skoo87/gitignore

added .gitignore file
fixed a bug in test case
Merge pull request #164 from dinic/concat

fixed a bug in test case
Merge branch 'master' of github.com:yzprofile/tengine
format the test case code
Merge pull request #161 from yzprofile/master

set prefix when start nginx