add new hier_config option ('no' commands exception)

[rbartzen]

Add a new option to replace the command line expression for specifics ios exceptions (regex) - negation case.
e.g. no ip access-list A seq B

[jtdub]

Hi @rbartzen -- Can you write a test case for this?
@jdrew82 -- does this fix #101 ?

[jdrew82]

This does look like it'd address that, though I think it'd be better if it applied to all lines, not just negations.

[gneville-ot]

I've come across use-cases for Juniper set style commands where we'd need to do this, for instance updating NTP servers for example:

Original Config

set system ntp server 1.1.1.1 routing-instance mgmt_junos

Intended Config:

set system ntp server 4.4.4.4 routing-instance mgmt_junos

hier_config will try:

delete system ntp server 1.1.1.1 routing-instance mgmt_junos
set system ntp server 4.4.4.4 routing-instance mgmt_junos

but that results in "system ntp server 1.1.1.1" just dropping the "routing-instance mgmt_junos" parameter.

admin@TEST# show | compare 
[edit system ntp server 1.1.1.1]
-    routing-instance mgmt_junos;
[edit system ntp]
+    server 4.4.4.4 routing-instance mgmt_junos;