Revert "temporary workaround sxls to support old servers"

This reverts commit b4fc8e610a9657716ec1af34ee1c39824716fd78.
Use time window for ETA computation

Keep information about current transfer speed in time window to properly
estimate finish time.

sxcp progress handling cosmetics (braces && indentation).
Code cosmetics

Change indentation.
Silence compiler warnings.
Change few local variables types from int to unsigned int that are used as array indices. That stops warnings about comparing signed and unsigned variables.
Print progress information to stderr instead of stdout

Summaries are printed to stdout
ugly hack for the notify filter
Fix too long total time for eta time window
3rdparty: update curl to 7.37.1
No Last-Modified on listfiles (it would go backwards on file removal)
Prevent nginx from stripping ETags when gzipping
Revert "3rdparty: update curl to 7.37.1"

This reverts commit 974e2c338ca8a1078cc1c07f10e03d9e01fda955.
rework timeouts
rework getfile
return mtime and revision on file get
Fix broken dash given as last argument
s/timeout/extra_timeout
3rdparty: update curl to 7.37.1 (bb#726)
make some function names more suitable (bb#401)
be consistent in requiring a secure connection (when available) for key ops (bb#407)
fix some memleaks
NSS: don't crash if the SSL callback is invoked too early
Fix file size reporting for sxcp reading from stdin.

Size of tempfile was set to 0, because it was reopened before closing.