Fix iOS id

iOS must use weighted predicates or it'll return the wrong result when multiple
elements share the same id.

For example:
id('sign_in_label').click currently matches a static text and a button. The
static text does nothing, so we'd prefer to return an element that has
interactive abilities such as the button.

If someone wanted to match the static text using an id anyway, they could do
s_text resolve_id 'sign_in_label'
Merge pull request #1116 from bootstraponline/ios_id

Fix iOS id
Try harder to find devices
Merge pull request #1119 from bootstraponline/protocol_fault

Try harder to find devices
add --ios-sdk flag to reset.sh to allow building with specific ios sdk ver
make it easy to switch test version for ios
change instruments timeout to something more reasonable
no need to wait 300s if instruments fails to launch
fix test for ios 7.0
Merge pull request #1120 from jlipps/master

more ios 7 compatibility updates
Fix --avd flag by removing double quotes (spawn doesn't like them, only exec)
Adding desired capabilities doc
Merge pull request #1122 from penguinho/avd_fix

Fix --avd flag by removing double quotes
Update caps.md
Fixing error thrown when trying to read Localizable.string off a real device
Must run safari on simulator before running appium

Fix #755
Merge pull request #1124 from penguinho/fix_real_devices

Fixing error thrown when trying to read Localizable.string off a real de...
MoveTo now moves to the center if no offset is provided
Merge pull request #1121 from penguinho/moveto_center_fix

MoveTo now moves to the center if no offsets are provided
update gappium
fix issue with touch/click on android getting wrong params