gtk3: Use current bee file template

Recreate bee file with the command below, and convert it to a
versionless bee file.

```
$ bee init https://ftp.acc.umu.se/pub/gnome/sources/gtk+/3.22/gtk+-3.22.26.tar.xz
creating gtk+-3.22.26-0.bee from template '/etc/default/bee/templates/fallback'
```

Add the configure switches back.

gtk3.be0

@@ -1,29 +1,56 @@
 #!/usr/bin/env beesh
 
-# BEE_VERSION gtk3-3.22.26-0
+# BEE_VERSION gtk+-3.22.26-0
+
+## this file was created by bee init and should be executed to build a
+## bee-package. (Additional hints are located at the end of this file.)
+
+###############################################################################
+## The source URL(s) define the location of the sources that will be
+## downloaded. Version variables may be used to simplify reuse of this bee-file.
 
 SRCURL[0]="https://ftp.acc.umu.se/pub/gnome/sources/gtk+/${PKGVERSION[2]}/gtk+-${PKGVERSION}.tar.xz"
 
-PATCHURL[0]=""
+###############################################################################
+## Add URLs/pathes to patch files to the PATCHURL array.
+## The sources will be patched in the order of the array.
+
+# PATCHURL+=()
 
-# BEE_CONFIGURE=compat
+###############################################################################
+## Add filename patterns to the EXCLUDE array of files that should not
+## be added to you package but may be present in the image directory.
 
-# BEE_BUILDTYPE=
+# EXCLUDE+=()
 
-# EXCLUDE=""
+###############################################################################
+## Uncomment the next statement, if the software may not be able to be built
+## outside the source directory and needs to be built inside the source
+## directory.
 
 # build_in_sourcedir
 
+###############################################################################
+## bee cannot detect buildtypes specified in subdirectories.
+## Sometimes packages "hide" the real sources in a subdirectory named
+## 'src' or 'cmake' or ..
+## use 'sourcesubdir_append' to specify this directory if known.
 
+# sourcesubdir_append src
 
 
+###############################################################################
+## Change the default (auto-detected) steps to
+## extract, patch, configure/setup, build and install the software.
+## Make sure the mee_install function does install everything to the
+## image directory "${D}"
 
 #mee_extract() {
-#    bee_extract ${@}
+#    bee_extract "${@}"
 #}
 
 #mee_patch() {
-#    bee_patch ${@}
+#    bee_patch "${@}"
 #}
 
 mee_configure() {
@@ -37,3 +64,22 @@ mee_configure() {
 #mee_install() {
 #    bee_install
 #}
+## by default this may be 'make install DESTDIR="${D}"'
+
+###############################################################################
+##
+## Additional hints:
+##
+## The name of this bee-file should follow the following naming convention:
+##     pkgname-pkgversion-pkgrevision.bee
+##
+## You may remove all comments as long as SRCURL[0] is set.
+##
+## Everything in this file will be executed in a bash environment.
+##
+## Build the package by executing
+##     './pkg-version-N.bee' or
+##     'beesh ./pkg-version-N.bee'
+##
+## see http://beezinga.org/
+##