Provide a group-name filter to get_all_security_groups() call.

This uses a helper method provided by starcluster instead of directly
calling the boto method.
Merge pull request #401 from mindprince/minor-improvement

Provide a group-name filter to get_all_security_groups() call.
add support for t2 instance types
Merge pull request #407 from rayrayson/develop

add support for t2 instance types
sshutils: pass socket timeout down to SCPClient
tests: fix for latest changes to pytest_cov

It seems with the latest changes to pytest_cov it's now impossible to
configure the coverage plugin exclusively from conftest.py without
manually loading and configuring the plugin in pytest_configure. Without
this the coverage plugin can ONLY be loaded/configured via the command
line arguments to pytest (which sucks btw). This change to pytest_cov
broke the build on travis-ci - this hack should fix that.
include pytest.ini in MANIFEST.in

closes #454
Don't crash if the connection has an error
set encrypted flag to None for root device

"AWS API doesn't support any value for this flag for the root device of
a new instance"

see: boto#2587

closes gh-455
move try/except from is_up to is_ssh_up
Merge branch 'fix-conn-reset-by-peer' into develop

closes #465
remove t2 types from placement group types list
bump version to 0.95.6
Changelog: update for 0.95.6 release
Merge branch 'hotfix-0.95.6' into develop
Merge pull request #1 from jtriley/develop

Sync with upstream changes