Better HTTP client support and more convenient macro

This release adds flexibility in configuring the HTTP clients, by allowing disabling HTTP client default features directly through the pretend-* crate. It also remove request and header attribute macros. Only pretend attribute macro is required to write pretend enabled traits. The other attributes will be handled automatically by pretend.

Changed

Added

• Disabled default features for HTTP clients (#37) @SfietKonstantin
• Removed request and header attributes (#25) @SfietKonstantin

Fixes

• Fixed tests (#41) @SfietKonstantin
• Enforced Rust 1.44 MSRV (#38) @SfietKonstantin
• Moved MSRV enforcements as separate test (#39) @SfietKonstantin