The `common` name is from the time where kiwix was only one repository
for all the project (android, desktop, server...).
Now we have split the repositories and kiwix-lib is the "common" repo,
the "common" directory is somehow nonsense.
The value is store as a string in in the xml, so we cannot use getAsI.
We have to get the string and parse it to an int.
We cannot use strtoull because android stdc++ lib doesn't have it.
We have to implement our how parseFromString function using a
istringstream.
- "winsock2.h" needs to be included before "windows.h". But if a
compilation unit include "windows.h" and after "networkTools.h", we
fails and it is complicated to handle. The include must not be in the
header but in the cpp
- windows define some ERROR macro. It is a pitty but we cannot use `ERROR`
in our enum.
- If build statically using mingw we need to define `CURL_STATICLIB`
The downloader is using libaria2.
For now, only one download can be run a the time.
A download will start only if (and as soon as) no download is running.