Add support for ILX Workspace management

[blagoySimandov]

Add support for ILX Workspace management

This pull request implements the feature request outlined in issue #105, adding support for ILX Workspace Creation, Deletion, Modification, and File Upload to the F5 BIG-IP Go SDK.

Changes Implemented

1. Added ILXWorkspace, ILXFile, and Extension structs in a new ilx.go file to represent ILX workspace components.
2. Implemented the following methods in the BigIP struct:
   • GetWorkspace(ctx context.Context, path string) (*ILXWorkspace, error)
   • CreateWorkspace(ctx context.Context, path string) error
   • DeleteWorkspace(ctx context.Context, name string) error
   • CreateExtension(ctx context.Context, opts ExtensionConfig) error
   • WriteExtensionFile(ctx context.Context, opts ExtensionConfig, content string, filename ExtensionFile) error
   • ReadExtensionFile(ctx context.Context, opts ExtensionConfig, filename ExtensionFile) (*ILXFile, error)
3. Added WriteFile and ReadFile methods to sys.go
4. Created a new example in cmd/ilx_workspace/example.go

Testing

• Manual testing has been performed with the new example in cmd/ilx_workspace/example.go.

Additional Notes

• The new example location (cmd/ilx_workspace/example.go) differs from the previous convention. This was done to address issues with outdated and non-functional examples in the previous location. I propose putting future examples under the cmd/(some_example_grouping)/example.go location and moving the old non-functional examples.
• The implementation uses the run command with echo and cat for file operations, which may need to be the best option.

Related Issue

Closes #105

Please review and let me know if any further changes or information are needed.