Introducing cookie based authentication

Solving issue #6, now, you can also use a session cookie to authenticate jira-sync, like
so:

jira-sync \
    --baseurl https://jira.myorganisation.com \
    --project MYPROJ  \
    --cookie JSESSIONID=… \
    --target issues/MYPROJ/raw \
    fetch

0.4.5

Removing debug output and unnecessary output.

0.4.4

Support for fetching attachments and rendering them to markdown.

v0.4.3

• Tightening timeout
• Denoise the output
• Adding a progress bar
• Fix exceptions to contain http status
• Improving readme

v0.3

• Adding formatting utility jira-format-issues
• Improved error messages