Try to invoke vcs before claiming source.
Try to invoke vcs before claiming source.

This should prevent errors that would occur with bad .git or
.hg folders present in the source trees.

jbradberry/dxr,jay-z007/dxr,jbradberry/dxr,pelmers/dxr,jay-z007/dxr,jbradberry/dxr,jay-z007/dxr,pelmers/dxr,pelmers/dxr,jbradberry/dxr,pelmers/dxr,pelmers/dxr,jbradberry/dxr,jay-z007/dxr,jbradberry/dxr,pelmers/dxr,jay-z007/dxr,jbradberry/dxr,jay-z007/dxr,jay-z007/dxr,pelmers/dxr