Changing order of requirements in order to ease the pain for non OSX newcomers.

requirements.txt

-gnureadline>=6.3.3
 requests>=2.9.1
 paramiko>=1.16.0
 beautifulsoup4>=4.4.1
-pysnmp>=4.3.2
\ No newline at end of file
+pysnmp>=4.3.2
+gnureadline>=6.3.3
\ No newline at end of file