QUIC: unroll and inline ngx_quic_varint_len()/ngx_quic_build_int(). According to profiling, those two are among most frequently called, so inlining is generally useful, and unrolling should help with it. Further, this fixes undefined behaviour seen with invalid values. Inspired by Yu Liu.

make -f misc/GNUmakefile release

the required tools:
*) xsltproc to build CHANGES,
*) xslscript.pl ( http://hg.nginx.org/xslscript ) to build XSLTs
   from XSLScript sources.


make -f misc/GNUmakefile icons

the required tool:
*) netpbm to create Win32 icons from xpm sources.