This fixes multiple issues with kdesrc-run and kdesrc-build --run

When using the --run parameter, the environment variables of global module were applied (from set-env options). But this is incorrect, since global cannot be treated as usual module. Its build system is defined as generic. In its prepareModuleBuildEnvironment these variables were setted:
- PKG_CONFIG_PATH
- LD_LIBRARY_PATH
- PATH
They have nothing to do with launched module's variables, except PATH, but even that was because of global install-dir matches the module's install-dir in most cases.

The kdesrc-run did sourced module's prefix.sh instead (located in its build-dir). That setted the following variables:
- PATH (the correct, from module)
- XDG_DATA_DIRS
- XDG_CONFIG_DIRS
- QT_PLUGIN_PATH
- QML2_IMPORT_PATH
- QT_QUICK_CONTROLS_STYLE_PATH

This commit fixes the broken behavior of --run, and the broken behavior of kdesrc-run.

Fixes: #145
Fixes: #114

Other fixes:
- Now the parameters after --run...