… definition directory alternative (DynamoDS#10208)

* Add common package folder location similar to common definitions directory to PathManager

* Initalize common package directory

* Add a list of root directories to verify certificates and check those before adding the package

* fix null value check

* Update comments

* Modify package and package loader to only check libraries defined in pkg.json manifest

* Check view extension for valid signed certificate if path matches root to check

* Upate extension loader to validate extension have valid certificate if they are found in directories requiring verification

* Rename package property for to RequiresSignedEntryPoints

* Fix bugs in package loader signed check

* Revise view extension / extension loading logic to avoid ext deff pointing to dll outside of check dir

* Comments

* Package PR comments

* Extension loading pr comments

* View extension pr comments

* On more comment

* Refactor .Net assembly cetificate verication to DynamoCrypto

* Consume validate method from DyanmoCrypto

* Add comments

* Move cert verification method to DynamoUtilities Class

* Add new CertificateVerification class to DynamoUtilities

* Update comments

* Extract package error messages to resource files

* Add comments and change RequiresSignedEntryPoints to internal

* Add test Cases for signed packages

(cherry picked from commit 717bb16)