Allow customizing the HTTP method of requesting the access token
Allow customizing the HTTP method of requesting the access token

Fixes a linkedin OAuth2 issue

See: http://developer.linkedin.com/forum/unauthorized-invalid-or-expired-token-immediately-after-receiving-oauth2-token

authomatic/authomatic,scorphus/authomatic,garg91824/authomatic,erasanimoulika/authomatic,liorshahverdi/authomatic,muravjov/authomatic,vivek8943/authomatic,scorphus/authomatic,touilleMan/authomatic,farcaz/authomatic,kshitizanand/authomatic,scorphus/authomatic,peterhudec/authomatic,dougchestnut/authomatic,garg91824/authomatic,vivek8943/authomatic,muravjov/authomatic,touilleMan/authomatic,authomatic/authomatic,artitj/authomatic,daherk2/authomatic,vivek8943/authomatic,farcaz/authomatic,erasanimoulika/authomatic,kshitizanand/authomatic,muravjov/authomatic,jasco/authomatic,dougchestnut/authomatic,erasanimoulika/authomatic,scorphus/authomatic,c24b/authomatic,leadbrick/authomatic,touilleMan/authomatic,liorshahverdi/authomatic,liorshahverdi/authomatic,farcaz/authomatic,daherk2/authomatic,leadbrick/authomatic,daherk2/authomatic,peterhudec/authomatic,kshitizanand/authomatic,dougchestnut/authomatic,leadbrick/authomatic,touilleMan/authomatic,leadbrick/authomatic,leadbrick/authomatic,c24b/authomatic,c24b/authomatic,peterhudec/authomatic,farcaz/authomatic,jasco/authomatic,artitj/authomatic,artitj/authomatic,authomatic/authomatic,jasco/authomatic,dougchestnut/authomatic,dougchestnut/authomatic,scorphus/authomatic,farcaz/authomatic,garg91824/authomatic