Enable ambiguous completion on first Tab press

The show-all-if-ambiguous setting is now enabled in /etc/inputrc.

Previously the setting was set to off, accompanied by the comment 'Show
all instead of beeping first'. The documentation for this setting says:

  This alters the default behavior of the completion functions. If set
  to ‘on’, words which have more than one possible completion cause the
  matches to be listed immediately instead of ringing the bell. The
  default value is ‘off’.

Since the setting is off by default and setting it to off does the
opposite of what the comment says, it looks like the intent was to
enable the setting and that it's disabled by mistake. The commit
message in ed01c26 ('Kills the annoying bell') where this setting was
originally added also suggests that the setting was intended to be
enabled.
Merge pull request #262 from yuvale/master

Set show-all-if-ambiguous to on
include etc/motd in portable git
Merge pull request #263 from bbodenmiller/patch-3

include etc/motd in portable git
Backport improved version of the shears from the Git for Windows SDK

The script was improved there, and for the moment, let's just get the
goodness back into msysGit, too, as long as we cannot make the final
jump to Git for Windows' SDK.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Fixed version in portablegit motd

When the version was added to the motd, it would come up as an empty space when using portable git as $version didn't exist. This makes it display the specified version.
Merge pull request #264 from Hobby-boy/patch-1

Fixed version in portablegit motd