newick.pyx: Fix overflow when reading very big trees.

When reading a tree from a file with more than 5 GB or so, using
the position as an int would overflow. It happened for example
with K01181_GTDB_rooted.faa.alg_annotated.nw.

Changing int -> long (in cython) for the position fixes the problem,
and has no appreciable bad impact on performance.

ete4/parser/newick.pyx

@@ -229,7 +229,7 @@ def loads(tree_text, parser=None, tree_class=Tree):
     return tree_class(props, nodes)
 
 
-def read_nodes(nodes_text, parser, int pos=0, tree_class=Tree):
+def read_nodes(nodes_text, parser, long pos=0, tree_class=Tree):
     """Return a list of nodes and the position in the text where they end."""
     # nodes_text looks like '(a,b,c)', where any element can be a list of nodes
     if nodes_text[pos] != '(':
@@ -256,7 +256,7 @@ def read_nodes(nodes_text, parser, int pos=0, tree_class=Tree):
     return nodes, pos+1
 
 
-def skip_spaces_and_comments(text, int pos):
+def skip_spaces_and_comments(text, long pos):
     """Return position in text after pos and all whitespaces and comments."""
     # text = '...  [this is a comment] node1...'
     #            ^-- pos               ^-- pos (returned)
@@ -274,7 +274,7 @@ def skip_spaces_and_comments(text, int pos):
     return pos
 
 
-def read_content(str text, int pos, endings=',);'):
+def read_content(str text, long pos, endings=',);'):
     """Return content starting at position pos in text, and where it ends."""
     # text = '...(node_1:0.5[&&NHX:p=a],...'  ->  'node_1:0.5[&&NHX:p=a]'
     #             ^-- pos              ^-- pos (returned)
@@ -291,7 +291,7 @@ def read_content(str text, int pos, endings=',);'):
     return text[start:pos], pos
 
 
-def skip_quoted_name(str text, int pos):
+def skip_quoted_name(str text, long pos):
     """Return the position where a quoted name ends."""
     # text = "... 'node ''2'' in tree' ..."
     #             ^-- pos             ^-- pos (returned)