replace uiElement.map_list with a richer widget that allows sorting

uses knockout but provides a similar interface to the uiElement functions
remove newly unused code
fix bug with session data in trialconnect reports
Merge pull request #1627 from dimagi/tc

fix bug with session data in trialconnect reports
Add new excel field type option for integers

Since excel stores all numbers as decimals, the importer can cause
problems with applications that are expecting integer types.
add toggle submodule and example for custom parent ref feature
Merge pull request #1624 from dimagi/parent-ref-toggle

add toggle submodule and example for custom parent ref feature
Merge pull request #1628 from dimagi/case-importer-ints

Add new excel field type option for integers
Merge pull request #1607 from dimagi/id-map-sorting

Id map sorting
tiny tweaks to copy_group_data
Merge pull request #1629 from dimagi/copy-group-data

tiny tweaks to copy_group_data
Merge branch 'master' into django-1.5-build