Rely on platform-provided versions. Thus, no need to download and
build them, neither to wrap them with shell scripts. CMake and
precommit updated to call the new tools. Development documentation
also updated/simplified.
PS: On my Ubuntu 14.04.3, cppcheck has version 1.61, while prereq
version was 1.69. The older version reports and fails on a strange
style issue in ecma/builtin-objects/ecma-builtin-helpers.cpp, for
which the only solution found was to suppress the cppcheck errors
with `variableScope` id for that file.
JerryScript-DCO-1.0-Signed-off-by: Akos Kiss akiss@inf.u-szeged.hu
