manuals: suppress excess use of "following" word

To simplify the style, replace "Following is" and "Following are"
by "here is" and "here are", sounding more natural.

In some cases, also go further by simplifying "Here are/is xxx"
by "xxx are/is" when the "are" or "is" are not two far at
the end of the sentence.

In some cases too, completely remove the sentence, when
it's redundant with the preceding title.

(From yocto-docs rev: 2539f1b9cbf9bdd40eff93c6522dc76133debed7)

Signed-off-by: Michael Opdenacker <michael.opdenacker@bootlin.com>
CC: Daniel Ammann <daniel.ammann@bytesatwork.ch>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

documentation/dev-manual/python-development-shell.rst

@@ -35,7 +35,7 @@ system were executing them. Consequently, working this way can be
 helpful when debugging a build or preparing software to be used with the
 OpenEmbedded build system.
 
-Following is an example that uses ``pydevshell`` on a target named
+Here is an example that uses ``pydevshell`` on a target named
 ``matchbox-desktop``::
 
    $ bitbake matchbox-desktop -c pydevshell