Update to new version of lzma and get it from kiwix.org server.

It seems that the downloading of the archive stored on sourceforge
fails sometime.

Use the archive stored in our server (download.kiwix.org) instead.
And also move to the last version of lzma.

kiwixbuild/dependencies/lzma.py

@@ -9,9 +9,9 @@ class lzma(Dependency):
     name = 'lzma'
 
     class Source(ReleaseDownload):
-        archive = Remotefile('xz-5.2.3.tar.bz2',
-                             'fd9ca16de1052aac899ad3495ad20dfa906c27b4a5070102a2ec35ca3a4740c1',
-                             'https://tukaani.org/xz/xz-5.2.3.tar.bz2')
+        archive = Remotefile('xz-5.2.4.tar.gz',
+                             'b512f3b726d3b37b6dc4c8570e137b9311e7552e8ccbab4d39d47ce5f4177145'
+                            )
 
     class Builder(MakeBuilder):
         @property

kiwixbuild/versions.py

@@ -35,12 +35,12 @@ release_versions = {
 
 # This is the "version" of the whole base_deps_versions dict.
 # Change this when you change base_deps_versions.
-base_deps_meta_version = '17'
+base_deps_meta_version = '18'
 
 
 base_deps_versions = {
   'zlib' : '1.2.8',
-  'lzma' : '5.2.3',
+  'lzma' : '5.2.4',
   'uuid' : '1.43.4',
   'xapian-core' : '1.4.10',
   'mustache' : '3.2',