Merge pull request pkg#470 from pkg/hotfix/constants-overflow-implici…

…t-32bit-types

Need to type constants that overflow `int` on 32-bit archs

Merge pull request pkg#467 from pkg/bug/missing-id-passthru-on-statfs

Missing ID passthru on statfs

Merge pull request pkg#452 from pkg/patch/fix-filezilla

[bugfix] FileZilla parses the directory listing in longname

Merge pull request pkg#439 from pkg/feature/ReadFromWithConcurrency

Export a ReadFromWithConcurrency function that permits ensuring concurrency usage.

Merge pull request pkg#410 from pkg/export-realpath

Export RealPath for potential client use

Merge pull request pkg#376 from pkg/update-go-mod-for-1-12

Update go.mod dependencies ahead of 1.12 release

Bugfix and small feature release.

First release in some time. Fixing lots of bugs and adds a few new
features. Below are the highlights.

Features:
* [pkgGH-301] support rename extension for server
* [pkgGH-332] Added a ClientOption to determine whether to use Fstat or Stat
* [pkgGH-315] make SFTP extensions configurable

Bugfixes:
* [pkgGH-291] Wrong S_IFMT mask when converting filemode bits to os.FileMode
* [pkgGH-295] sftp resume produces corrupted files
* [pkgGH-298] Extensions are not announced by the server
* [pkgGH-329] fix S_IFMT value on windows, plan9 and js/wasm
* [pkgGH-325] Request.Attributes() panics when called with the Attr slice empty
* [pkgGH-309] fix: received packet too long

Thanks to all the contributors. Your time and patience is appreciated.

go modules update

make client more resilient with servers that don't support full protocol

client can now detect sftp connection close

Implments a clintConn.Wait() method.
Fixes: pkg#278

Thanks @wutzx for the PR.

fixes tests to run on windows