Add 'cainfo_path' option to 'storj_http_options'

[kaloyan-raev]

The 'cainfo_path' options sets the path to the Certificate Authority (CA) bundle. The value is then used to set the CURLOPT_CAINFO option to avoid the CURLE_SSL_CACERT error on systems (like Android) that have no suitable CA bundle.

I need this for the Android app I am developing. I can pack the CA bundle in the APK, extract it on a suitable location on the Android device upon app startup and then pass this location as 'cainfo_path' option to libstorj.

[braydonf]

We've typically handled these errors via a compiling step of libcurl, see https://github.com/Storj/libstorj/blob/master/depends/packages/libcurl.mk though this could be useful too.

[kaloyan-raev]

Do you mean to compile libcurl with the --with-ca-bundle=FILE option?

The problem with this approach is that there is no built-in CA bundle on Android. I have to pack it in the app's APK and the unpack it on app's startup. I can unpack it to the app's data dir, but the exact location of this data dir is determined during runtime. It is not a good idea to fix the location during compile time.