Updates to the docs
Minor bug fix to feedback during validation, more unit tests and a couple of broken file paths.
Minor update to the docs.
Update credits
Bug fix and further test cases to ATInt.  Thanks to Matti Pauna and Anna Kairema for reporting this problem.
Improvements to catching common syntax errors with trig functions, e.g. sin^-1(x) or cos[x]
Update the experimental code to remove "filter" and swap this for "sublist".  Does not affect the main code base.
Extra test case added.
Merge branch 'master' of https://github.com/maths/moodle-qtype_stack

Conflicts:
	tests/inputfixtures.class.php
Update project history.
Bug fix to ATInt
Merge branch 'master' of github.com:maths/moodle-qtype_stack
Refactor two numerical answer tests, NumRelative and NumAbsolute, to work within answertest_general_cas.
Expand numerical tests ATRelative and ATAbsolute to accept lists and sets of numbers.
Add a summary to the bottom of the healthcheck.
STACK should delete the temporary plot files each time an image is created.
Updates to the docs.
Add the option to set the type of parentheses for matrices.
Ignore whitespace surrounding forbidden keywords in the input options.
Fix a bug in the question tests for single character which prevented the teacher entering a test case which has more than one character (and hence using the question variables).