Bump fakefs

Fakefs compatible with ruby 2.1.1 is not released yet, so
we are using the gem from source at github.

- Switch to StringIO instead of /dev/null for Logger in specs, as this
  conflicts with new Fakefs expecting /dev/null to exist
- Test changing directories to be independent of current spec directory
- Fix Fakefs expand path issue:
  In new Fakefs path and expanded path are not the same

Signed-off-by: Maria Shaldibina <mariash@pivotallabs.com>
Remove $SAFE level for ERB parsing

$SAFE=4 level was removed from ruby 2.1.1. In general, this SAFE level
does not provide enough security.

Signed-off-by: Maria Shaldibina <mariash@pivotallabs.com>
Update shell_spec const stubbing
Use temp directory in errands controller spec

Some environments resolve paths differently; make sure that director
has access to base_dir as configured.

Signed-off-by: Maria Shaldibina <mariash@pivotallabs.com>
Add ruby-2.1.1 to travis integration build

Signed-off-by: Maria Shaldibina <mariash@pivotallabs.com>
Increase timeout for agent start in tests

Signed-off-by: Maria Shaldibina <mariash@pivotallabs.com>
Add GOROOT to travis:go_install

Signed-off-by: Maria Shaldibina <mariash@pivotallabs.com>