Fixing RemotingTest - delete temp failed during teardown

...on Windows (in Eclipse).
Proof: hierarchy branch behaviour still does not work

"remotes/origin/master" still does not work correctly (depending
on the branches in the repo.

If "remotes/origin/abc/master" does exist configuring
"remotes/origin/master" still fails because only "master" is extracted
from the branch spec which again matches for both branches.

Btw. git ls-remote lists the branches alphabetically. Therefore
"master" is listed before "test/namespace1/master".
That's why I had to rename the test branches in order to reproduce the
issue.
Fix for hierarchical branch issue (last commit)
Added test for branch names using "reserved" keywords

Test for getHeadRev with branch names which SHOULD BE reserved by Git,
but ARE NOT. E.g. it is possible to create the following LOCAL (!)
branches:
- "origin/master" results in refs/heads/origin/master
- "remotes/origin/master" results in refs/heads/remotes/origin/master
- "refs/heads/master" results in refs/heads/refs/heads/master
- "refs/remotes/origin/master" results in
  refs/heads/refs/remotes/origin/master
Fix for previous branch issue + general reserved branch names

Tests work for Cli client, but not yet for JGit client.
test_getHeadRev_reservedBranchNames uses test repo now

The test repo is contained in src/test/resources.
Therefore no repo preparation needed anymore.
test_getHeadRev_reservedBranchNames works for CliGit and JGit
Fixed and improved tests
namespace branch tests using repo from resources

+ all tests green now
+ some improvements
Cleaning unneccessary import changes