Add logFunction option

Can pass in a function to override default rollbar.js behavior and
instead pass payload to this logFunction instead of over the network to
Rollbar
Add logToConsole option

Uses window.console.log if defined to route payloads to that function,
using this.options.logFunction.
Merge branch 'master' into logToConsole

Conflicts:
	dist/rollbar.amd.min.js
	dist/rollbar.commonjs.min.js
	dist/rollbar.min.js
	dist/rollbar.shim.min.js
	dist/rollbar.snippet.min.js
Update README
Add dem spaces
Change spaces
Execute logFunction directly. Reset console.log in test.
issue #28 @brianr
docs @brianr
Merge pull request #44 from rollbar/enabled_flag

issue #28 @brianr
Update README.md
release v1.1.4
implement #26 @brianr
implement #41 #43 @brianr
fix bug introduced with wrap() context changes
Merge pull request #45 from rollbar/transform_and_wrap_context

Transform and wrap context
Update configuration.md
added _wrappedSource extra data key so we can see what the wrap() function is calling. @brianr
Merge pull request #46 from rollbar/wrapped_function_source

added _wrappedSource extra data key so we can see what the wrap() function is calling
release v1.1.6