Some small changes

[YuriyPobezhymov]

This PR tries to resolve few problems:

• Some WAFs reject requests without default UserAgent;
• Splitting header's key-value sometimes incorrect, for example when Referer header used;
• Temporary solution for splitting several headers by two semicolons, because some headers can contain semi-colon (better is to use curl way how to handle this), like UserAgent;

Thanks, Yuriy.

[hakluke]

Awesome this looks great @YuriyPobezhymov! Good point about the headers. Could you please update the -h help text to include two headers with the double semi-colon separation, and also update the readme?

[YuriyPobezhymov]

Ok, updated.

[hakluke]

Awesome - thanks @YuriyPobezhymov !!