Update RailoAjax.js

1) function "Railo.Json"
variable "escapable" now includes the chars "&" and "+"

2) function "Railo.ajaxProxy.invokeMethod"
test:
if (a[k])
changed to:
if (a[k] || a[k] === 0 || a[k] === "" )
to include params that equal 0 and ""
Merge branch 'master' of https://github.com/cmosdall/railoajax into cmosdall-master
merge https://github.com/andreacfm/railoajax/pull/5
Merge branch 'cmosdall-master'