OP-1258 update toolchain installer for Linux to 4.8-2013q4, change ARM_SDK_DIR accordingly
OP-1258 updated to 2014q1, also allow to manually specify MD5 file url

Conflicts:
	make/tools.mk
OP-1258 make TOOL_INSTALL_TEMPLATE md5 url optional so that it defaults to fileurl.md5
OP-1258 fix an issue with Windows package (root folder is missing in the zip file)
OP-1258 fix an issue with all_sdk_install on windows (still pointing to deprecated targets)
Merge branch 'amorale/OP-1258_gcc_4.8-2014-q1' into next
OP-1287 changed default offsets for better behaviour with vtolpathfollower - needs to be increased to 500 on horizontal and 5 veetical for use with fixedwings
Merge branch 'next' into corvuscorax/OP-1287_PositionVario