Merge "Modify TestCase.__str__() to use PrettyTable"

diff --cc requirements.txt
Simple merge

diff --cc test-requirements.txt
index 088b387,f68a56f..76e475d
--- 1/test-requirements.txt
--- 2/test-requirements.txt
+++ b/test-requirements.txt
@@@ -23,6 -23,7 +23,7 @@@ pyyaml==3.1
  requests==2.8.0
  robotframework==2.9.1
  robotframework-requests==0.3.8
 -robotframework-sshlibrary==2.1.1
 +robotframework-sshlibrary==2.1.3
  subprocess32==3.2.7
  virtualenv==15.1.0
+ PrettyTable>=0.7.1,<0.8 # BSD