Support change from urllib2 to requests lib.

Commit f809f91 changed the fileclient from urllib2 to requests. To properly build a .deb package we need to add python-requests to the build dependencies.
Merge pull request #11837 from bretep/patch-5

Support change from urllib2 to requests lib.
Require python-requests for install
Merge pull request #11839 from bretep/add-requests-to-debian-build

Require python-requests for install
Better variable names.
Merge pull request #11838 from s0undt3ch/develop

Better variable names.
Merge branch 'develop' of github.com:saltstack/salt into develop