Change version number to 3.4.0

This patch updates the html documents.
This patch also re-enables testing with Intel Compiler.

This patch updates the copyright year of files.

This patch adds the following functions.

* fastsinf_u3500
* fastcosf_u3500
* fastpowf_u3500
* log2_u35, log2f_u35
* exp2_u35, exp2f_u35

The error bound of fastsin and fastcos are max(2e-6, 350ULPs).
Each function has corresponding deterministic functions.

Currently a no-op but this makes it easier to support vector call attribute on x86,
which might be necessary on windows.

Add missing VECTOR_CC for sincos

On rare occasions, the error with sin_u10 and cos_u10 functions exceeds 1.0 ULP.
This patch fixes this problem.

This patch adds sin, cos, tan, exp, exp2, exp10, expm1, log, log2, log10, log1p, asin, acos, atan, comparison functions and cast functions between quad and double to libsleefquad.

Remove vectorcc from getInt and getPtr declarations

These functions are not defined with vectorcc so they shouldn't be declared with it either.

This patch replaces Horner method which was used to evaluate polynomials with Estrin's method( https://en.wikipedia.org/wiki/Estrin%27s_scheme ) that allows more parallel computations with out-of-order execution.
This patch also introducing a new reduction method to tan.
With this patch, mainly computation for double-precision functions becomes faster, and the effect is like a few percent to 20 percent. For example, the ratio between execution time of the following functions before and after applying this patch is shown below.

Sleef_atan2d4_u35 : 1.21
Sleef_powd4_u10 : 1.17
Sleef_sind4_u35 : 1.10
Sleef_tand4_u10 : 1.04
Sleef_tand4_u35 : 1.17

This patch adds Sleef_strtoq and Sleef_qtostr which can be used to convert between a quad value and a string. These functions are not vectorized. The corresponding testers are also added.

This patch also adds functions for subtraction.

Intel compiler testing is temporarily disabled because of license expiration( https://github.com/shibatch/sleef/issues/238 ).

This is a part of implementation of issue #233 ( https://github.com/shibatch/sleef/issues/233 ).
At this point, add, mul, div and sqrt with testers are implemented. Remaining functions will be committed in the succeeding PRs.
As for vector extensions, SSE2, AVX, FMA4, AVX2, AV2_128, AVX512F, AdvSIMD and SVE are supported.

This quad-precision math library is built only if -DBUILD_QUAD option is given to cmake. For some time(1 year?), this sub-project is positioned at alpha development stage.

1. `-march=armv8-a+simd` is removed as it is not necessary (#232)
2. Delete output that is never generated (#231)

It also includes changes of CI setting for removing GCC/OSX testing on travis. This is because updating gcc with brew takes too much time now. Instead of this, build with gcc is now tested on Jenkins.

Merging 3.3.1 with aavpcs

The x86 dispatcher was build for SP when targeting DP.

This commit enables building `libsleef` and `libsleefgnuabi` with the
`aarch64_vector_pcs` attribute defined in the _Vector Function ABI
specification for AArch64_ [1].

The build must be configured with `-DFORCE_AAVPCS=On`. By default this
configure variable is set to `Off`.

[1] https://developer.arm.com/products/software-development-tools/hpc/arm-compiler-for-hpc/vector-function-abi

This patch reduces testing time to 50%.

I found a bug of tester in denormal/nonnumber handling of functions with two arguments.
This patch fixes that bug.
There is no change in the library itself.