Pywebexec

* manage simple quote in json for dict params

* dict params to json

- schema_options separator to separator_params:
- `separator_params: {"*": " ", "param2": "="}`
- produces: `command --param1 value1 --param2=value2
- `separator_params: {"param2":"="} convert_params: {"param2":"param2}`
- produces: `command --param1 value1 param2=value2`

* adjust range slider / description

* -C --cols
* -R --rows
* batch mode uses terminal cols/rows to spawn commands

* css range value adjust