Merge pull request #1095 from palfvin/master

Remove "its" support as part of rspec-core issue #1083
Fix warning about ambiguous argument.
Merge pull request #1096 from vipulnsward/fix_ambiguous_warning

Fix warning about ambiguous argument.
use const_get to load formatters
remove eval from spec
remove eval with case statement for common usage, potentially breaking change
older versions of ruby dont seem to like const_get used in this fashion, this is arguably better than eval?
comment on default value
allow symbol tag values
refactor to gsub
Merge pull request #1097 from rspec/remove_more_evals

Remove more evals