platform: put bossac in own section

Author: facchinm

platform.txt

@@ -104,18 +104,19 @@ tools.dfu-util.upload.params.quiet=
 # -Q introduced with latest dfu-util
 tools.dfu-util.upload.pattern="{path}/{cmd}" --device {upload.vid}:{pid.0},:{upload.pid} -D "{build.path}/{build.project_name}.bin" -a{upload.interface} -Q
 
+tools.bossac.path={runtime.tools.bossac-1.9.1-arduino5.path}
+tools.bossac.cmd=bossac
+tools.bossac.upload.params.verbose=-d
+tools.bossac.upload.params.quiet=
+tools.bossac.upload.pattern="{path}/{cmd}" {upload.verbose} --port={serial.port.file} -U -e -w "{build.path}/{build.project_name}.bin" -R
+
 # Required discoveries and monitors
 # ---------------------------------
 pluggable_discovery.required.0=builtin:serial-discovery
 pluggable_discovery.required.1=builtin:mdns-discovery
 pluggable_discovery.required.2=builtin:dfu-discovery
 pluggable_monitor.required.serial=builtin:serial-monitor
 
-tools.bossac.path={runtime.tools.bossac-1.9.1-arduino5.path}
-tools.bossac.cmd=bossac
-tools.bossac.upload.params.verbose=-d
-tools.bossac.upload.params.quiet=
-tools.bossac.upload.pattern="{path}/{cmd}" {upload.verbose} --port={serial.port.file} -U -e -w "{build.path}/{build.project_name}.bin" -R
 
 # Debugger configuration (general options)
 # ----------------------------------------