Change speed calculation if download speed equals 0

The formula used to convert bytes per second to human readable
units uses Math.log(speed), which is undefined (or -Inifinity)
when speed equals zero. So don't use that formula if speed equals
zero.
Merge pull request #151 from runeksvendsen/dev-0.3

Change speed calculation if download speed equals 0
Temp fix: Force DB refresh at each load

Actually i’ll force a DB refresh at each load but we need to add
something to compare version with the api and if changed we resync. (we
can use the same endpoint as the update.json for this) We also need to
add a TTL (1day) to the last sync (if structure didn’t changed) to
limit the # of query to our endpoint.
Hide resize subtitles buttons while trailer is playing
Revert commit 636cccdd808a1e5426a1e4051417bb8772d64a4f
Make api get better quality of cover-image and uncrop close button, should fix #136 (NOTE: You need to empty AppData/Local/Popcorn-Time for the cover-image quality change to take effect)
Fix quality button positioning in trailer video player, forgot to do this with yesterday's fix.
Merge pull request #156 from DJScias/dev-0.3

Make api get better quality of cover-image and uncrop close button, shou...
Merge pull request #153 from G-Ray/resize-btn

Hide resize subtitles buttons while trailer is playing
Merge pull request #150 from iNoX-/dev-0.3

Center the movie list
fixe the episodes list show
remove tag that is no need
Update show_detail.styl
Update show_detail.styl
Center show-list and fix movies centering
Show-list is now centered and movie-list is centered when coming back from TV Shows.