nss: propagate blocking direction from NSPR I/O

... during the non-blocking SSL handshake
INFILESIZE: fields in UserDefined must not be changed run-time

set.infilesize in this case was modified in several places, which could
lead to repeated requests using the same handle to get unintendent/wrong
consequences based on what the previous request did!
build: Added Visual Studio 6.0 (VC6) project files

Carrying on from commit 11025613b9 added a more thorough version of
the VC6 project files which are capable of supporting side-by-side
compilation, as well as support for some of the third-party libraries
curl uses.
build: Added Visual Studio .NET (VC7) project files

Carrying on from commit 11025613b9 added VC7 project files which are
capable of supporting side-by-side compilation, as well as support for
some of the third-party libraries curl uses.
build: Corrected libcurl PDB file name for x64 builds in VC8 through VC12
build: Added other VC6 output files to the .gitignore list
http2: Compile with latest nghttp2

commit 6d5f40238028f2d8c (Apr 27) or later nghttp2 is now required
unit1395: Fixed null pointer dereference on torture test
Added a few more const where possible
runtests.pl: Improved the check for a crash during torture tests
copyright: Updated following recent edits
build: Added Visual Studio project file generator

Added a batch file for generating the Visual Studio project files from
the new template files.
build: Added VC9 and VC10 support to the project file generator
build: Added VC11 support to the project file generator
build: Added VC6 and VC12 support to the project file generator
build: Added VC7 and VC7.1 support to the project file generator

Note: VC7.1 templates are currently not available.
build: Fixed generation when source file names contain spaces

This shouldn't happen with the source files in the repository, but
fixed the output when there are spurious files lying around that
contain spaces. For example "pop3 - Copy.c"

By including the offending source file in the project files the user
can then see the file and remove it if necessary.
test585: Fixed NULL pointer dereference in fopen
build: Added Visual Studio 2003 .NET (VC7.1) project files

Carrying on from commit 11025613b9 added VC7.1 project files which are
capable of supporting side-by-side compilation, as well as support for
some of the third-party libraries curl uses.
build: Added OpenSSL VC build helper for side-by-side compilations