Support various VCS systems

This links VCS registry to the subproject model, so that it can choose
which VCS to use.

Issue #511
Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/trans/migrations/0011_auto_20141114_1008.py

+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+import weblate.trans.validators
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('trans', '0010_source_check_flags'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='subproject',
+            name='vcs',
+            field=models.CharField(default=b'git', help_text='Version control system to use to access your repository with translations.', max_length=20, verbose_name='Version control system', choices=[(b'git', b'Git'), (b'mercurial', b'Mercurial')]),
+            preserve_default=True,
+        ),
+        migrations.AlterField(
+            model_name='source',
+            name='check_flags',
+            field=models.TextField(default=b'', blank=True, validators=[weblate.trans.validators.validate_check_flags]),
+            preserve_default=True,
+        ),
+    ]

weblate/trans/models/subproject.py

@@ -33,7 +33,7 @@ from weblate.trans.formats import FILE_FORMAT_CHOICES, FILE_FORMATS
 from weblate.trans.mixins import PercentMixin, URLMixin, PathMixin
 from weblate.trans.filelock import FileLock
 from weblate.trans.util import is_repo_link, get_site_url, cleanup_repo_url
-from weblate.trans.vcs import GitRepository, RepositoryException
+from weblate.trans.vcs import RepositoryException, VCS_REGISTRY, VCS_CHOICES
 from weblate.trans.models.translation import Translation
 from weblate.trans.validators import (
     validate_repoweb, validate_filemask,
@@ -90,6 +90,16 @@ class SubProject(models.Model, PercentMixin, URLMixin, PathMixin):
         'Project',
         verbose_name=ugettext_lazy('Project'),
     )
+    vcs = models.CharField(
+        verbose_name=ugettext_lazy('Version control system'),
+        max_length=20,
+        help_text=ugettext_lazy(
+            'Version control system to use to access your '
+            'repository with translations.'
+        ),
+        choices=VCS_CHOICES,
+        default='git',
+    )
     repo = models.CharField(
         verbose_name=ugettext_lazy('Source code repository'),
         max_length=200,
@@ -461,7 +471,7 @@ class SubProject(models.Model, PercentMixin, URLMixin, PathMixin):
             return self.linked_subproject.repository
 
         if self._repository is None:
-            self._repository = GitRepository(self.get_path())
+            self._repository = VCS_REGISTRY[self.vcs](self.get_path())
 
         return self._repository