Fixes the following GCC/Clang warnings:
```
modules/gdnative/nativescript/nativescript.h:280:37: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
modules/gdnative/nativescript/nativescript.h:281:37: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
modules/gdnative/nativescript/nativescript.h:283:42: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
modules/gdnative/nativescript/nativescript.h:285:38: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
modules/gdnative/nativescript/nativescript.h:287:38: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
modules/gdnative/nativescript/nativescript.h:290:45: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
modules/gdnative/nativescript/nativescript.h:291:44: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
```
- Bundle editor dependencies:
- 'GodotSharp': Root data directory for the editor
- 'Tools': Editor dependencies. Only GodotSharp.dll for now.
- 'Api': Prebuilt GodotSharp and GodotSharpEditor API assemblies.
- 'Mono': Mono files to bundle with the editor.
- 'bin': (Optional, not used for now) Mono bin directory.
- 'etc': Mono configuration files.
- 'lib': Mono dependency shared libraries.
- 'lib/mono/4.5': Framework assemblies.
- Added build option to copy the required files from the mono installation to 'GodotSharp/Mono'. Enable with 'copy_mono_root=yes'. Disabled by default.
- Export template dependencies:
- 'data_AppName'/'data_Godot':
- 'Mono': Mono files to bundle with the game.
- 'etc': Mono configuration files.
- 'lib': Mono dependency shared libraries.
- The data directory is generated when compiling and must be bundled with the export templates. In the case of OSX, the data directory must be placed inside the 'osx.zip' export template.
- In OSX, alternative location for directories (needed for app bundles) are:
- 'data_AppName/Mono/etc' --> '../Resources/GodotSharp/Mono/etc'
- 'data_AppName/Mono/lib' --> '../Frameworks/GodotSharp/Mono/lib'
- The editor can bundle prebuilt API assemblies.
- Generate them with a tools build by running: `--generate-cs-core-api <GodotSharp_OutputDir> --generate-cs-editor-api <GodotSharpEditor_OutputDir> <GodotSharp_OutputDir>/bin/Release/GodotSharp.dll` (This command will be simplified in the future and both projects will be in the same solution)
- Build the solutions and copy the output files to '#bin/GodotSharp/Api'.
- Fixed API assembly being added twice during the export process.
Disabled signed/unsigned warnings like for GCC/Clang
(warning C4018: '>=': signed/unsigned mismatch).
Fixes the following MSVC 2017 warnings:
```
core\image.cpp(999): warning C4804: '>': unsafe use of type 'bool' in operation
core\io\compression.cpp(178): warning C4334: '<<': result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?)
editor\doc\doc_dump.cpp(226): warning C4334: '<<': result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?)
scene/resources/material.h(289): warning C4334: '<<': result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?)
scene/resources/material.h(298): warning C4334: '<<': result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?)
editor\editor_themes.cpp(379): warning C4805: '==': unsafe mix of type 'int' and type 'bool' in operation
```
Fixes the following Clang 7 warnings:
```
core/io/marshalls.cpp:872:10: warning: unused variable 'f' [-Wunused-variable]
core/ustring.cpp:1831:2: warning: 'register' storage class specifier is deprecated and incompatible with C++17 [-Wdeprecated-register]
core/ustring.cpp:1832:2: warning: 'register' storage class specifier is deprecated and incompatible with C++17 [-Wdeprecated-register]
drivers/gles3/rasterizer_gles3.cpp:82:24: warning: unused function '_gl_debug_print' [-Wunused-function,34]
main/main.cpp:118:13: warning: unused variable 'auto_build_solutions' [-Wunused-variable]
modules/csg/csg_gizmos.cpp:225:46: warning: 'current' may be used uninitialized in this function [-Wmaybe-uninitialized]
```
