fixes #1361 -- Add gateway and dns fields to Subnets

• Allow subnet values to be accessed in provisioning templates

fixes #1422 - Media is greyed out when creating Solaris hosts

fixes #1421 - expose subnet ranges for automatic IP address allocations

fixed dashboard pie colors.

fixes #1414 - pie is over cooked in chrome.

fixes #1411 - hostgroup ajax actions are mostly broken

refs #1406 - missed html_safe on 500 error page

Revert "Fixes #944 - clear network conflicts"

This reverts commit 117ba92a758e4589ef5fdf1f1b9083402b2d317b.

Fixes #944 - clear network conflicts

When a network conflict is detected (such as conflicting ip/name dns or
dhcp records), foreman would try to suggest a resolution.

Signed-off-by: Paul Kelly <paul.ian.kelly@googlemail.com>

fixes #1406 - excpetion errors are not showin in the UI