Allow to run cmd task from custom location.

[schlamar]

This works automatically if you launch the first instance via the bat file. If this should work via context menu integration, you have to set the CMDER_ROOT environment variable.

[dbowring]

See #30 for alternate solution

[jazzzz]

With #30 Cmder always start in the user home dir, whereas this pull request allows to open Cmder in any directory, which is really useful.

There is just one thing missing in this pull request, the paths should be absolute in Cmder.bat (see commit f325855)

[schlamar]

Done in /~https://github.com/schlamar/cmder/pull/1
(I can send a PR from another fork to my own fork, really nice Github 👍 )

[samvasko]

whops, I balled up the merging 😕
but It works! Thanks

[jazzzz]

Commit ee50cc5 breaks this by forcing the initial directory to %USERPROFILE%.

[samvasko]

Oh, so can we combine the behavior?

[schlamar]

We could set the start dir in the bat but not in the task.