TAC-366: adjusting swipe_velocity of hammer

__ULTIMATE PROBLEM:__
The page is not changing on page swipes as internal users are expecting it to 

__HOW IT WAS FIXED:__
Modify the hammerjs swipe_velocity option
this value was experiment with, and discovered to make swipe to change page perform better

__TESTING SUGGESTIONS:__
Use a swift document viewer in read only mode (so the annotations module does not overlay and use its hammerjs instead)
1. build `wf-js-document-viewer` `master`
2. open document viewer landing page `/doc_viewer` and select a read only document
3. get a feel for how sensitive swiping is
4. in `wf-js-document-viewer`, point `bower.json` `wf-uicomponents` to this branch
5. run grunt
6. refresh document
7. flick/swipe to scroll pages
8. swiping to scroll pages should be more sensitive

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__FYA:__  @timmccall-wf @lancefisher-wf @ryanhanks-wf @brianreed-wf @danielbank-wf @clairesarsam-wf 
__FYI:__ @justindrolet-wf 

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