Made Base64 decoding constant-time (with regards to actual data byte contents).
Added guard code to avoid issue when decoding PEM but not keeping data.
Added intermediate casts to void* to prevent spurious warnings (with Clang and -Wcast-align).
New Makefile structure; added compatibility with Windows + Visual C + nmake.
Added certificate name extraction API (from subject DN and SAN extension).
Fixed handling of CR+LF line endings in PEM objects.
Initial import.