provide ext-gettext

[glensc]

this way this package could solve dependecy issues of packages having "require":"ext-gettext"

altho for this fully to work, would need to register functions in global namespace as well

[smmoosavi]

This lib provide __ and _gettext functions. But ext-gettext provide many other functions. you can see list of them. it seems that "provide":"ext-gettext" is not correct option for this lib.
For adding this option, I must define all ext-gettext's functions and pass all text case defined by ext-gettext.

[gggeek]

See https://github.com/gggeek/polyfill-gettext for a proper attempt at polyfilling the php extension