removed image load handlers on dispose
removed image load handlers on dispose

to prevent exception if gallery disposes and image not loaded yet
chunchill/PhotoSwipe,zonayedpca/PhotoSwipe,kaskajp/PhotoSwipe,SureShinde/PhotoSwipe,Xephi/PhotoSwipe,blazoncek/PhotoSwipe,dimsemenov/PhotoSwipe,pedro-mendonca/PhotoSwipe,Maverbelle/PhotoSwipe,duchaiweb/PhotoSwipe,thien0291/PhotoSwipe,kana7/PhotoSwipe,thorstein5/PhotoSwipeX,blazoncek/PhotoSwipe,dtyleung/PhotoSwipe,Magl/PhotoSwipe,luksak/PhotoSwipe,phillipalexander/PhotoSwipe,thorstein5/PhotoSwipeX,candybanana/PhotoSwipe,Magl/PhotoSwipe,zutrinken/PhotoSwipe,andygoo/PhotoSwipe,jonathanbell/PhotoSwipe,zutrinken/PhotoSwipe,englishextra/PhotoSwipe,agliottone/PhotoSwipe,dimsemenov/PhotoSwipe,fabiosantoscode/PhotoSwipe,SureShinde/PhotoSwipe,EagerApps/PhotoSwipe,duchaiweb/PhotoSwipe,chunchill/PhotoSwipe,bmk10/PhotoSwipe,bmk10/PhotoSwipe,candybanana/PhotoSwipe,johanronn77/PhotoSwipe,thien0291/PhotoSwipe,fabiosantoscode/PhotoSwipe,EagerApps/PhotoSwipe,ermakovmaxim/PhotoSwipe,Maverbelle/PhotoSwipe,digitalreasoning/PhotoSwipe,bhuber2010/PhotoSwipe,Zayebatsu/PhotoSwipe,briandamage/PhotoSwipe,englishextra/PhotoSwipe,kana7/PhotoSwipe,Xephi/PhotoSwipe,briandamage/PhotoSwipe,luksak/PhotoSwipe,johanronn77/PhotoSwipe,bhuber2010/PhotoSwipe,ermakovmaxim/PhotoSwipe,fredDesign/PhotoSwipe,andygoo/PhotoSwipe,jonathanbell/PhotoSwipe,zonayedpca/PhotoSwipe,phillipalexander/PhotoSwipe,dtyleung/PhotoSwipe,digitalreasoning/PhotoSwipe,kaskajp/PhotoSwipe,Zayebatsu/PhotoSwipe,pedro-mendonca/PhotoSwipe,fredDesign/PhotoSwipe