Compile with libcurl support

[eb]

Should change the Travis build to include libcurl, so that results reporting works out of the box.
Less urgent, but would be good: also build with libcurl support for Windows (use dynamic linking).

[fzwoch]

On Linux this should be as easy as just installing some of the libcurl-dev providers. On Windows it may need some meson.build adjustments unless you manage to use pkg-config there too.

[fzwoch]

Found in travis file:

  # ensure we do not have curl dev libs, otherwise it caused cross compilations to fail	
  - sudo apt-get -y remove libcurl.*-dev libpcre*-dev

While i tried to build for ARM on my machine:

The Meson build system
Version: 0.55.3
Source dir: /home/fzwoch/code/mvdsv
Build dir: /home/fzwoch/code/mvdsv/xxx
Build type: cross build
Project name: mvdsv
Project version: undefined
C compiler for the build machine: cc (gcc 10.2.0 "cc (Debian 10.2.0-15) 10.2.0")
C linker for the build machine: cc ld.bfd 2.35.1
C compiler for the host machine: arm-linux-gnueabihf-gcc (gcc 10.2.0 "arm-linux-gnueabihf-gcc (Debian 10.2.0-9) 10.2.0")
C linker for the host machine: arm-linux-gnueabihf-gcc ld.bfd 2.35.1
Build machine cpu family: x86_64
Build machine cpu: x86_64
Host machine cpu family: arm
Host machine cpu: armv7hl
Target machine cpu family: arm
Target machine cpu: armv7hl
Run-time dependency threads found: YES
Did not find pkg-config by name 'arm-linux-gnueabihf-pkg-config'
Found Pkg-config: NO
Found CMake: NO
Run-time dependency libpcre found: NO (tried pkgconfig and cmake)
Run-time dependency libcurl found: NO (tried pkgconfig and cmake)
Library m found: YES
Library dl found: YES
Build targets in project: 1

Found ninja-1.10.1 at /usr/bin/ninja

So it correctly detects that no cross-compile pkg-config is found and skips that feature on these platforms. So it does not use the system installed ones.