added uploading attachments to emailcompose for saving and sending messages
updated customFileInput-plugin, but disabled it because rendering issues with file fields in formsets
disabled clickFocus-plugin for <input type=file />
adds attachmentformset to emailcompose
fixes issues with multiple formsetviewmixins where mixins are added to classes instead of instances
moved 'fixing' the formhelpers to a new base formsetviewmixin from DeleteBackAddSaveFormViewMixin
removed SublimeText 2 package from gitignore