#1515: Update computed properties to avoid deprecated method

[FergusInLondon]

Fixes #1515

Description

To pre-empt the upcoming deprecation of fn().properties(...) for computed properties, all usages have been removed and replaced with the correct Ember.computed(..., fn()) method.

Tests

All tests pass on Solus Linux, using Node 6.14.4.

1..1603
# tests 1603
# pass  1603
# skip  0
# fail  0

# ok

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cc @HospitalRun/core-maintainers

[jsf-clabot]

All committers have signed the CLA.

[donaldwasserman]

👍 Looks great. Thanks for the help!