add escript win32 alternative invocation (thanks Pierre Rouleau)

On Windows, escript may be passed different arvg[0] values depending
on how it was started up.

This patch allows for escript to be started as "escript.exe"
(current behaviour) and also "escript" which is more likely when
called from the default Windows cmd.exe shell.
[megaco] Fixed faulty test case (connect)
Fixes value returned by mnesia_loader:do_get_disc_copy2/4

Returns the same value for `mnesia_loader:disc_load_table/2' as
`mnesia_loader:net_load_table/4' if a table copy can not be found.

This patch was stuck as a pull request in GitHub (authored by Uwe
Dauernheim):
	https://github.com/erlang/otp/pull/16
Fix returned error from gen_tcp:accept/1,2 when running out of ports

The {error, enfile} return value is badly misleading and confusing for
this case, since the Posix ENFILE errno value has a well-defined meaning
that has nothing to do with Erlang ports. The fix changes the return
value to {error, system_limit}, which is consistent with e.g. various
file(3) functions. inet:format_error/1 has also been updated to support
system_limit in the same manner as file:format_error/1.
Avoid creating an undefined start_phases entry when generating a release

When a release is generated and the applications in the release do not
define a value for the start_phases entry of their .app files, reltool
will generate the following entry in the .app files of the release:

{start_phases, undefined}

If this happens, when trying to create a release upgrade systools will
fail because it doesn't allow the start_phases entry to be set to
undefined. This patch avoids this situation by not generating a
start_phases entry when it is set to undefined.
[inets/httpd] Add server tokens config option

Added ability to configure the server software
header field (with the server_tokens config option).
OTP-9805
[inets] Added more error info when connect fails
[inets] Added more (printed) system info during test case init

Print some host info (os, os-type and sys arch and so on)
during test case init.
[inets] Moved (dbg) trace utility functions to own module (inets_trace)
[inets] Improved error handling in test case
[inets] Added verbosity printout to improve error detection

Added verbosity printouts to detect error reason for
file access error on windows.
[inets] Testing IPv6 support on windows...
[inets] Conditionally exec functions, testing for local host IPv6 support
[inets] Add preliminary "has IPv6 support" info to TC config
[inets] System Info printouts in test suite

Moved the System Info printout to the init_per_suite function
for the httpc suite. Added it to the same function for the
httpd suite.
[inets] Improved test util error handling when copy dirs

Copy dirs failed for some cases, so added more info when
that happens. Also added more info during httpd test case
init.
Merge branch 'bmk/inets/httpd/configurable_server_tokens/OTP-9805' into bmk/inets/inets59_integration
Merge branch 'bmk/inets/httpc/checking_ipv6_on_windows' into bmk/inets/inets59_integration
[inets] Proper appup

OTP-9805
Merge branch 'bmk/inets/httpd/configurable_server_tokens/OTP-9805' into bmk/inets/inets59_integration

Conflicts:
	lib/inets/src/inets_app/inets.appup.src