Turn modified fdlibm into Jerry's own libm

* Rename modified fdlibm to jerry-libm
  * Move third-party/fdlibm to jerry-libm
  * Rename original fdlibm.h to jerry-libm-internal.h
    * And remove it from the public headers.
  * Rename jerry-libm's public header to math.h
    * This also makes jerry-core sources include `<math.h>`. Therefore,
      should anyone want to use a different libm implementation with
      jerry, it becomes possible. (The same way as we provide a minimal
      libc with standard headers, but should it be insufficient or
      conflicting for someone, it can be replaced.)
  * Drop `s_` prefix from jerry-libm sources
    * The original fdlibm implementation had various prefixes (e.g., `k_`
      for sources of kernel routines, and `w_` for wrapper routines), but
      after the specialization of fdlibm to jerry, only `s_` remained.
      Since it does not encode anything anymore, it can be dropped.
  * Stylistic edits to jerry-libm's CMakeLists
    * Align project name with other CMakeLists in the code base
  * Move Jerry-LibM under Apache License
    * Using the same approach as was used by linux-wireless when ath5k
      driver license needed clarification. Solution was proposed by SFLC.
      External mail for future reference: http://lwn.net/Articles/247806/

* Tests & checks
  * Remove FD from the name of libm unit test-related files
  * Make vera++ and cppcheck check jerry-libm

* Targets
  * Speculative update of targets to use jerry-libm

JerryScript-DCO-1.0-Signed-off-by: Akos Kiss akiss@inf.u-szeged.hu

tools/check-cppcheck.sh

@@ -25,9 +25,10 @@ fi
 
 JERRY_CORE_DIRS=`find jerry-core -type d`
 JERRY_LIBC_DIRS=`find jerry-libc -type d`
+JERRY_LIBM_DIRS=`find jerry-libm -type d`
 
 INCLUDE_DIRS=()
-for DIR in $JERRY_CORE_DIRS $JERRY_LIBC_DIRS
+for DIR in $JERRY_CORE_DIRS $JERRY_LIBC_DIRS $JERRY_LIBM_DIRS
 do
  INCLUDE_DIRS=("${INCLUDE_DIRS[@]}" "-I$DIR")
 done
@@ -38,4 +39,4 @@ cppcheck -j$CPPCHECK_JOBS --force \
  --error-exitcode=1 \
  --exitcode-suppressions=tools/cppcheck/suppressions-list \
  "${INCLUDE_DIRS[@]}" \
- jerry-core jerry-libc *.c *h tests/unit
+ jerry-core jerry-libc jerry-libm *.c *h tests/unit