add margin() function to composer menu, fixes #343
Merge pull request #876 from obfuscurity/add_margin_function_to_composer

Add margin() function to composer menu
Implements missing minimumBelow() render function

As discussed (for over a year) on issue #255, minimumBelow() is missing
which is odd as it's counterparts are all there. This change
implements that function and adds it to the composer.
Merge pull request #878 from ojilles/master

Implements missing minimumBelow() render function
Overlooked one minimum/maximum discrepancy (fixed on 0.9.x already).
This would leave a confusing documentation :-D
Merge pull request #882 from ojilles/master

Overlooked one minimum/maximum discrepancy (fixed on 0.9.x already).
ignore trailing args in aliasByMetric(), fixes #862
Merge pull request #884 from obfuscurity/fix_trailing_commas_aliasByMetric

Ignore trailing args in aliasByMetric(), fixes #862
remove refs to nonexistent images, fixes #689
Merge pull request #891 from obfuscurity/fix_dashboard_panel_gif

Remove ref to nonexistent images, fixes #689
Remove use of 'autoescape off'
Fix XSS in ?showTarget parameter
Remove use of '|safe' in templates in favor of mark_safe()
Merge pull request #896 from brutasse/fix/autoescape

Remove use of autoescape and |safe in templates
Add a pathExpression to constantLine
Merge pull request #898 from markolson/give-constantline-a-pathExpression

Add a pathExpression to constantLine
clarifiying areaBetweens arg expectation, & how to use the  function with it
removing a trailing space
Merge pull request #899 from gwaldo/clarify_areaBetween

clarifiying areaBetweens arg expectation, & how to use the group function with it
initial version of 0.9.13 release notes, refs #893