Released version 0.11.2

NOTE: pypi package doesn't include #236 and #245 however to
avoid rewritting git history we include this commit for
reference purposes.
Define two new levels of aggregatation for older pings.
Fixes #549. Handle 'profile' parameter on media type.
Avoid URL access to duplicate slice and node on sliver addition.
Typo on 404 message.
Typo on controller version.
Move resource-list renderer to generic URIList. Fixes #276 note 23
Cosmetics.
Fixes #273. Implement media type profile matching.
Generate binary versions of certificate (#410)

Include binary certificate and key files on firmware generation.
Fix PEM to DER export command for certificate (#410).
Merge branch 'bug410'
Handle malformed profile on media type negotiation.
Removed defaults for SFA data (#427)
Fix addition of list to tuple (#427).
Merge branch 'bug427'
Show unavailable sliver ifaces with the cause (#216).
Show ifaces forbidden reason on batch sliver creation.
Use node resources data to determine ifaces availability.
Tests #216: create interfaces is_allowed unittests.