added tests for timeout behavior

Tests for correct behavior when estimateSize times out and fails
for any other reason
Factored out timeout handling
fixed whitespace
# Please enter the commit message for your changes. Lines starting
# with '#' will be ignored, and an empty message aborts the commit.
# On branch dl_estimate_speed_fixes
# Changes to be committed:
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#	modified:   src/test/javascript/portal/cart/DownloadEstimatorSpec.js
#	modified:   src/test/javascript/portal/cart/DownloadPanelItemTemplateSpec.js
#	modified:   web-app/js/portal/cart/DownloadEstimator.js
#
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#	web-app/js/GeoExt1.1/resources/images/default/anchor_new.png
#	web-app/js/GeoExt1.1/resources/images/default/anchor_top_new.png
#	web-app/js/portal/cart/.vagrant/
#	web-app/js/portal/cart/Vagrantfile
Added newline at end of file
Changes made to unit tests as per review
Unit tests actually work now
Unit tests actually work now
Merge pull request #911 from aodn/dl_estimate_final_fix

Handles timeouts in estimateSizeForLayer