Fix null value handling in /insert

Merge pull request #107 from visenze/feature/null_im_url

fix null value handling during insert

add browse gallery api

Merge pull request #106 from visenze/feature/browse_gallery

[ES-10134] add new browse galellery api

Http proxy setting, allow override of app key and placement ID

Merge pull request #105 from visenze/feature/proxy_setting

[ES-10066] add setting http proxy to client config, allow override of app_key and placement_id in base params

Pin hide enhancements response fields

Merge pull request #104 from visenze/feature/pin_enhacements

[API-10051] Update response fields for pin hide enhancements

Multisearch autocomplete API

Merge pull request #103 from visenze/feature/multisearch

[API-9945] Multisearch support

Multisearch API

Merge pull request #102 from visenze/feature/multisearch

[API-9945] Multisearch support

Add non_product_based_recs param

Merge pull request #100 from visenze/feature/non_product_based_recs

[API-9725] add non_product_based_recs param

Add box_type to response

Merge pull request #99 from visenze/feature/box_type

[API-9548] add box_type in response

Add category list param for Recommendations

Merge pull request #98 from visenze/feature/category_param

[API-9276] Add category list param for STG custom box(es)

Don't send default values for null request params

Merge pull request #97 from visenze/feature/default_params

[API-9195] don't send parameters default value if not proviided