COMP: address clang -Winconsistent-missing-override in ITKQuadEdgeMesh

Change-Id: Id5a7e1a72aa314cf75b726c47cf5c96958b94730
STYLE: Put ImageToImageFilterCommon in its own file.

This also simplifies wrapping.

Change-Id: I46e5d787bd902a78389329401babf605ae929f78
BUG: Wrap ImageToImageFilterCommon.

Change-Id: I27e384984604ce0a19b0d8d195743e929ea0df34
STYLE: Put ImageSourceCommon in its own file.

Change-Id: I2cb7d1b78410e6e59c04f46384b0202b28950075
DOC: Edits for the beginning of chapter 5, Statistics

Change-Id: I3069c9dbdcd5f503d0ef5c11717487c9ffc75bb3
Merge topic 'wrap-warnings'

83dc7e54 STYLE: Put ImageSourceCommon in its own file.
590aa25c BUG: Wrap ImageToImageFilterCommon.
08ab5dfe STYLE: Put ImageToImageFilterCommon in its own file.
Merge topic 'WarningQuadEdgeMesh'

f24b6680 COMP: address clang -Winconsistent-missing-override in ITKQuadEdgeMesh
Merge topic 'book-2-chapter-5'

72994ecf DOC: Edits for the beginning of chapter 5, Statistics