ProxSuite 0.2.5

What's Changed

• C++14 compliant implementation of optional by @fabinsch in #78
• C++14 compliant implementation of aligned_alloc by @fabinsch in #79
• unittest/sparse-ruiz: replace checks with isApprox by @fabinsch in #83
• Fix packaging for pip by @jcarpent in #82
• Move optional.hpp to the right place by @jcarpent in #81
• Fix logic and bug in warm_start by @jcarpent in #85

Full Changelog: v0.2.4...v0.2.5