Created test case for the replaceTabs API.
Merge pull request #82 from pentateu/topic/replaceTabs_api_memory_issue

Topic/replace tabs api memory issue
Added test cases for drawer when calling layers.push and layers.replace
Merge pull request #85 from pentateu/topic/layers_drawer_fix

Topic/layers drawer fix
Added new test cases for when a preloaded web view push or replace layers while outside the statck.
Merge branch 'topic/native_bridge_default_layer_fix' of github.com:pentateu/steroids-js into topic/native_bridge_default_layer_fix