Resolve #152 and partially #148

I'm not quite done with either of these, but this commit:
- Reduces leakage per 148
- Fixes send_keys per 152
- Addition of mobile command for 152 to allow for bringing back the old behavior

To come:
- More permanent fix for 148

Sorry about the mess, I'm still getting the hang of branch/rebase/etc. in git... next changes will be more appropriately branched/managed.