fix($drag): offset dragged element relative to first positioned ancestor

[adam77]

fixes #63
Notes:

• $dndPosition is a stripped down version of $position from angular-ui/bootstrap.
• Removed draggable.positionAbs as it didn't appear to be in use.
• Fixed a bug in draggable when using jqlite that showed up in the new test (relevant jqlite bug: docs(angular.element): css() api incompatibility. angular/angular.js#11614).
• Manually tested OK in IE9.

At some point the DOM utils stuff could be merged with $dndPosition perhaps.

[coveralls]

Coverage increased (+23.94%) to 100.0% when pulling f8b138d on adam77:offset-fix into 97e2cae on caitp:master.

[coveralls]

Coverage increased (+23.94%) to 100.0% when pulling f8b138d on adam77:offset-fix into 97e2cae on caitp:master.

[adam77]

heh, can't argue with those coverage stats.

[caitp]

definitely, that's awesome. Let me take a look at this

[caitp]

I was previously putting helpers like this in src/utils.js --- if moving them here and refactoring, please delete the old dead code and make sure this new code is being used consistently

[coveralls]

Coverage increased (+1.39%) to 77.45% when pulling 515c10f on adam77:offset-fix into 97e2cae on caitp:master.

[coveralls]

Coverage increased (+1.39%) to 77.45% when pulling 515c10f on adam77:offset-fix into 97e2cae on caitp:master.

[coveralls]

Coverage increased (+1.39%) to 77.45% when pulling 8ad1df4 on adam77:offset-fix into 97e2cae on caitp:master.

[coveralls]

Coverage increased (+1.39%) to 77.45% when pulling 8ad1df4 on adam77:offset-fix into 97e2cae on caitp:master.

[caitp]

something got messed up with the coveralls account --- could you rebase and re-push? I just want to see the accurate coverage info before landing

[coveralls]

Coverage increased (+23.94%) to 100.0% when pulling 32fda40 on adam77:offset-fix into 97e2cae on caitp:master.

[coveralls]

Coverage increased (+23.94%) to 100.0% when pulling 32fda40 on adam77:offset-fix into 97e2cae on caitp:master.

[caitp]

the coverage looks okay (non-regression at least), although for whatever reason coveralls is not reporting the new file on their UI (they seem to be suffering from some new bugs lately!)

[adam77]

i noticed the new travis file has node v0.1?

[caitp]

it's the same as 0.10, it's just formatted differently

[caitp]

The demo still works nicely, so as far as I'm concerned it's safe to merge --- it would be good to add to the demo app with a little showcase of your fix. LGTM, landing