Various fixes before 3.0

- Fix .ini formatting issues in tox.ini file
- Updated developer docs regarding testing
- Add missing requirements for xosapi
- Fix typo in docs

Change-Id: I3603bbd68c8ecff68d8bbc1a2d4674908c54e5b9
diff --git a/tox.ini b/tox.ini
index d78bf8b..ea5235b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -22,10 +22,6 @@
 [unittest]
 plugins = nose2.plugins.junitxml
 code-directories =
-  xos-genx
-  xos-api
-  xos-config
-  xos-synchronizer
   coreapi
 
 [junit-xml]
@@ -34,5 +30,6 @@
 [coverage]
 always-on = True
 coverage = xos
-coverage-report = term
-coverage-report = xml
+coverage-report =
+  term
+  xml