Update GNMI Go dependency (#281)

update gnmi dependency (#280)

Fix an age-old bug with `FromFloat` handling of negatives. (#268)

* Fix an age-old bug with `FromFloat` handling of negatives.

 * (M) pkg/yang/types_builtin(_test)?.go
    - This change squashes a bug that has existed for a long time
      in `FromFloat`, but only shows up on arm64. I finally have an
      arm64 machine and so found the issue. It was originally reported
      in openconfig/ygot#766. The issue is
      that uint64 of a negative float64 is undefined  -- and on arm64
      on darwin returns 0, which made some test cases fail only on this
      architecture.

* Add missing comment.

* `gofmt`

Added modifier sub statement to pattern - rfc7950#section-9.4.5.1 (#241)

* Added modifier substatement to pattern - rfc7950#section-9.4.5.1

* gofmt

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Co-authored-by: wenovus <wenbli@google.com>

Protect `entryCache` with lock (#262)

* Protect entryCache with lock

If ToEntry() is called concurrently after entryCache is cleared with
ClearEntryCache(), then it is possible for a panic to occur as
entryCache is being concurrently read/written.

Fixes #261

* Add getEntryCache() and setEntryCache()

Add ClearEntryCache() to Modules (#260)

This function clears the entryCache in Modules to free up memory
after processing modules. entryCache is used by the ToEntry function
to cache previously converted nodes.

Fixes #259

Fix panic if module by prefix is not found in Find() (#252)

Previously, if FindModuleByPrefix() returns nil in Find(), it would
continue to call module() with nil, resulting in a nil pointer
dereference panic when trying to call ParentNode() from RootNode().
The fix is to return an error if FindModuleByPrefix() returns nil.

Fixes #251

initialize RPC input and output entries when augmented (#250)

* initialize RPC input and output entries when augmented

* set kind field

Skip empty files when parsing (#246)

Retain Extra fields over Uses,Augments (#244)

* Retain Extra fields over Uses,Augments

* Fix duplication issue; add IfFeature test for uses in augment

* Add comments to entry_test