Assemblies loading for Policy Evaluator and Checkintool improved. Refs #258
Move the path resolver to the constructor.

This will ensure that it's in place before evaluating
checkin policies, which is when it is needed, without
expanding the interface of ITfsHelper.
Check to install resolver only once
Correct case where one repository path is included in another one

When we are in a remote that have tfs path $/Project/MyBranch_1
and that we search the path in the git repository of the file $/Project/MyBranch_1.1/file.txt
we must return null (because this file is owned by the other remote $/Project/MyBranch_1.1)

In the past, we return ".1/file.txt" as relative path.

We should also managed well, folder path "$/Project/MyBranch_1.1" compare to "$/Project/MyBranch_1"
Same thing when using Subtree command
Merge pull request #603 from pmiossec/Support_branch_with_similar_name

Support branch with similar name
Merge pull request #573 from KindDragon/checkintool

Assemblies loading for Policy Evaluator and Checkintool improved