template: fix the root CMakeLists.txt

- remove references to VLE_DEPS*, variables that are no more built
- add boost libraries PATH
template: fix CMake script

VleCheckPackage config required that both an include directory and a lib
directory. Now, only one of them is required (taking into account for
example header only packages).
gvle: fix the configuration of oov

The data used for configuring the oov were remvoved when launching from gvle.
API of vpz has been extended with a function that modifies only the location
of an Output (Closes #99).
gvle: fix the rename function of the FileTreeView

The wrong variable was used as old path in the call of Package::rename.
(Closes #98)
gvle: fix file copy into the FileTreeView

The line that copies files was missing into onPaste function
(Closes #100)
gvle: fix the unhandled copies

Copy/paste feature only works if the target is a file with a file extension.
In case the target did not follow these requirements a std exception was
thrown. Instead we now do nothing. (Closes #101)