Clean up spelling, punctuation, and grammar in README
update performance table according to latest optimization, update readme
optimization: cpuid is bad instruction for performance - cache it
check __SSE2__ for gcc/clang sse intrinsics
Merge pull request #4 from manxorist/no-underscore-cpuid
Rename __cpuid to minimp3_cpuid because double underscore names are reserved in C.
rename MIN() & MAX() defines to avoid collisions
add MINIMP3_MAX_SAMPLES_PER_FRAME define
test: patch he_mode vector (fate have buggy version?)