[feature request] Enabling CI build (AppVeyor) and static analyzers (QC+Landscape)

This is my first relatively successful attempt to enable AppVeyor build ([1.1.3build3](https://ci.appveyor.com/project/pywinauto/comtypes/build/1.1.3build3)) on 8 Pythons. AppVeyor uses `Windows Server 2012 R2 (x64)`.

The results are not bad for Py2.7, but require some attention.

```
Ran 96 tests in 59.926s (10 modules skipped)
Unavailable resources: CRASHES, devel, events, memleaks, pythoncom, time, typelibs, ui

FAILED (failures=4)
```

Python 3.x tests completely fail (looks like not so hard to fix).

```
Traceback (most recent call last):
File "setup.py", line 143, in
dist = setup(**setup_params)
File "C:\Python34\lib\distutils\core.py", line 148, in setup
dist.run_commands()
File "C:\Python34\lib\distutils\dist.py", line 955, in run_commands
self.run_command(cmd)
File "C:\Python34\lib\distutils\dist.py", line 974, in run_command
cmd_obj.run()
File "setup.py", line 66, in run
self.refcounts)
File "build\lib\comtypes\test\__init__.py", line 190, in run_tests
skipped, testcases = get_tests(package, mask, verbosity)
File "build\lib\comtypes\test\__init__.py", line 89, in get_tests
for modname in find_package_modules(package, mask):
File "build\lib\comtypes\test\__init__.py", line 76, in find_package_modules
for fnm in package.__loader__._files.keys():
AttributeError: 'SourceFileLoader' object has no attribute '_files'
```

Static code analyzers might also be useful for the project.
- [Landscape.io health check](https://landscape.io/github/vasily-v-ryabov/comtypes/1) (done on Py3)
- [Quantified Code issues](https://www.quantifiedcode.com/app/project/gh:vasily-v-ryabov:comtypes)