Bump version to 0.40
[SystemInfo]: Fix crash in wifi network module on desktop.

This commit fixes the deletion of pointer owning by GVariant.
[SystemInfo] : Initialize the plugin instance only when need.

Moved plugin instance initialization from CreateExtension() to CreateInstance().

XW_Initialize/CreateExtension is intended to call by the xwalk extension server
while registering the extension with the server. CreateInstance() is called
when exactly the api is accessed by application, so this is the point where we
need to initialize extension.
Merge pull request #275 from avalluri/master

SystemInfo extension module fixes
Bump version to 0.41
Fix build for x64 arch

media_info_get_size waits unsigned long long not uint64_t
even if it seems to be the same in 32 bits arch.

=> int media_info_get_size(media_info_h media, unsigned long long *size)

log:

[   27s] content/content_instance.cc: In member function 'void ContentItem::init(media_info_h)':
[   27s] content/content_instance.cc:313:38: error: invalid conversion from 'uint64_t* {aka long unsigned int*}' to 'long long unsigned int*' [-fpermissive]
[   27s]    if (media_info_get_size(handle, &ll) == MEDIA_CONTENT_ERROR_NONE)
[   27s]                                       ^

BUG=https://crosswalk-project.org/jira/browse/XWALK-1346

Signed-off-by: Baptiste DURAND <baptiste.durand@open.eurogiciel.org>
Merge pull request #276 from eurogiciel-oss/XWALK-1346

Fix build for x64 arch
Bump version to 0.42