This commit:
- removes std-srvs and rosgraph-msgs recipes, as their sources
now are located in the ros_comm_msgs repository.
- adds a recipe for the new roslz4 package, which rosbag-storage
depends on.
- removes the patch that has been merged upstream.

The description is not indented after line breaks. All other
information, i.e., the dependencies and SRCURI, are indented with
four spaces after line breaks. Shell scripts are indented with
multiples of four spaces.

In recipes-ros, I located and checked for tabulators and spacing
with these bash commands:

egrep '^ [^ ]+' . --exclude *.patch -R
egrep '^  [^ ]+' . --exclude *.patch -R
egrep '^   [^ ]+' . --exclude *.patch -R
egrep '^    [ ]+[^ ]+' . --exclude *.patch -R

While going through the recipes and manually improving the layout,
I also adjusted the descriptions to use maximal 100 characters
per line.

After running oe-stylize.py on all recipes in recipes-ros, this
commit improves the formatting of some recipes.

To achieve this, I executed these commands in recipes-ros:
find . -name *.bb | sed 's#\(.*\)#./oe-stylize.py \1 > \1_sanitized#' | sh
find . -name *.bb | sed 's#\(.*\)#diff -Naur \1 \1_sanitized#' | sh > diffs

Then, I manually inspected the diffs file, and improved the
recipes.

For the DESCRIPTION line in the addressed recipes, the line width
of 100 characters was chosen, as the LIC_FILES_CHKSUM line and
SRC_URI line usually are also around about 100 characters long.
Hence, choosing a shorter line width, e.g. 80 characters, would
have only created more line breaks, but not reduced the need to
use a file viewer with which 100 characters line width can be
displayed. For the github file and diff viewer and most editors
on reasonably-sized screens, 100 character line width is no
problem.

Besides updating ros-comm, this commit removes the second hash
values, that probably slipped-in during the last update.

The ros-comm 1.9.53 now also contains the new package rosbag-storage.

The ros-comm recipes are updated to 1.9.50 to be in line with
https://github.com/ros/rosdistro/blob/ef3a7449d7f7ef6e691a5724ef6c485e75cfd4af/hydro/release.yaml.

The ros-comm recipes are updated to 1.9.48 to be in line with
https://github.com/ros/rosdistro/blob/4551e7c32d1b34984410b79bc0ec36afe3d3d245/hydro/release.yaml.
The previously applied patches have been included in 1.9.48 and are
removed from the recipe and this repository.

Signed-off-by: Stefan Herbrechtsmeier <stefan@herbrechtsmeier.net>

As the license text of the xmlrpcpp changed, the license checksum
is adjusted.

Signed-off-by: Stefan Herbrechtsmeier <stefan@herbrechtsmeier.net>