adding in ability to retrieve priorties list from Jira API

Change-Id: I35b7dcad0085e8cadf98afe46846e723d135cc56
Allow upload of attachments to Jira via CurlClient
Remove old code that was used to upload files
add ability to retreive statuses from Jira
Merge pull request #4 from addersuk/master

Add ability to return priorties from Jira