Django version upgrade plus features

[gladiatx0r]

Bulk push/merge to include recent changes in DART to the public repository. The full set of changes made are as follows;

• Updated Django to v1.11 to mitigate vulnerabilities in older version. Made changes to code base to compensate for framework changes and deprecations. Updated Bootstrap version and settings accordingly.
• Implemented feature enabling the ordering of supporting data (attachments).
• Implemented feature which tracks when forms are dirty and warns users when navigating away.
• Implemented feature for configuring an event identifier prepended to test case ID
• Updated report generation such that text in tables will be left aligned instead of justified
• Fixed bug in test order sort code which would erroneously change custom sort orders upon report generation
• Fixed bug where some template conditionals were erroneously using the wrong logical operator to check for equality
• Cleaned up report generation of test case ID when a custom test case identifier is not in use