Upgrade Haml to prevent it from mutating our strings.

https://bugzilla.redhat.com/show_bug.cgi?id=1134863

Haml 4.0.3 was doing gsub! on provided strings and was broken with frozen Strings.  It was fixed in 4.0.4 and 4.0.5 in this commit: https://github.com/haml/haml/commit/5bb46925b2b5211c7cb2052b8772872689e25346

Note: I had to run `bundle update haml brakeman` to get upgraded to 4.0.5 haml locally.
Upgrade net-ldap for fix for LDAP Controls.

https://bugzilla.redhat.com/show_bug.cgi?id=956833

net-ping at 1.5.3 required net-ldap at ~>0.2.2, so we need to upgrade net-ping also.

See: https://github.com/ruby-ldap/ruby-net-ldap/pull/18

In upgrading from 0.2.2 to latest, 0.7.0, the change we need is here:
https://github.com/ruby-ldap/ruby-net-ldap/compare/v0.2.2...v0.7.0#diff-724e0b3130dc49ca34eadc7c25d28b18R1647.
We want to be able to compact any nil control_codes.
UI Provision code to filter instance types

https://bugzilla.redhat.com/show_bug.cgi?id=1133780

The instance types are filtered based on the virtualization
type specified in the AMI. Each instance can support 1 or more
kind(s) of virtualization: hvm, paravirtual. Each AMI has a
virtualization type, so based on the selected AMI we can whittle
down the list of applicable instance types.
Removed Inherits from field from Add/Edit class screen.

https://bugzilla.redhat.com/show_bug.cgi?id=1138859
https://bugzilla.redhat.com/show_bug.cgi?id=1138744
Merge pull request #512 from mkanoor/bugzilla_1133780_provisioning

UI Provision code to filter Amazon instance types
Merge pull request #503 from jrafanie/upgrade_haml_to_not_mutate_strings

Upgrade Haml to prevent it from mutating our strings.
Merge pull request #505 from jrafanie/upgrade_net_ldap

Upgrade net-ldap for fix for LDAP Controls.
Merge pull request #517 from h-kataria/remove_inherits_from_class_add_edit_screen

Removed Inherits from field from Add/Edit class screen.