Fixed issue with cleaning deep dir structures

Order matters when recursively deleting directories, for one
project kept getting:
"An error occured in task The directory is not empty."
solved this by recursively deleting bottom up, it might be a bit
slower, but ensures delets are done in correct order.
Fix comment typo
Merge pull request #46 from devlead/patch-1

Fixed issue with cleaning deep dir structures.
MSBuild fix property multiple value & quotation
1.Added support for multiple values as some MSBuild properties require this
2.Addded quatation to property key / values to support values with spaces
3.Adjusted tests to pass with new sematics
This enables properties like ReferencePath to be used whith cake.
Example fluent:

    MSBuild(solution, settings =>
        settings.SetPlatformTarget(PlatformTarget.MSIL)
            .UseToolVersion(MSBuildToolVersion.NET45)
            .WithProperty("ReferencePath", @"c:\temp\assemblies1")
            .WithProperty("ReferencePath", @"c:\temp\assemblies2")
            .WithTarget("Build")
            .SetConfiguration(configuration));

Example all att once:

    MSBuild(solution, settings =>
        settings.SetPlatformTarget(PlatformTarget.MSIL)
            .UseToolVersion(MSBuildToolVersion.NET45)
            .WithProperty("ReferencePath", @"\temp\assemblies1", @"\temp\assemblies2")
            .WithTarget("Build")
            .SetConfiguration(configuration));
Merge pull request #47 from devlead/msbuild-properties

MSBuild fix property multiple value & quotation.
Added logging of process launch parameters. Closes #23.
MSBuild runner: Added support for max CPU count. Closes #50.
Minor code cleanup.
Using explicit version of Fake, since something seem to be wrong with 3.0.0.
Zip: Fixed bug with relative paths.
Added AssemblyInfo creator.
Updated release notes and increased version number.
Replaced FAKE with Cake (finally).
Now setting MSBuild tool version in build script.
Fixed TeamCity build number in build script.
Refactor and cleanup of script runner.
Added parsing of FAKE's complex release notes format.
Added parsing of FAKE's simple release notes format.
Fix for #58.
Removed unnecessary entries in .gitignore.