Clarification of which environment tests are run in
Added teamcity reporter

Added a reported for the TeamCity environment, allow tests to be
reported in TeamCity.
updated the news.md file

updated the news.md file to include the new TeamCityReporter.
Enable devtools mode
Merge pull request #120 from kforner/master

fixed a bug in SummaryReporter when label or info are vectors at the source
Re-document and tweak news
Merge pull request #119 from windelinckx/master

Added teamcity reporter
Merge pull request #118 from wch/env-doc

Clarification of which environment tests are run in
Update docs and tweak news
Put reporters in own category of news
Export reporter accessors.
Closes #102
Add expect_null. Closes #78
Use consistent strategy for generating test env.
Part of fixing #111
Use globalenv as parent env for tests.
Closes #111
Add expectation for testing names.
Closes #79
Merge and squash. Closes #77
Tweak documentation & functionality of new expes