updated to cygwin-20190322 -- package required by ocaml_setup for zarith;

--- a/Admin/components/bundled-windows	Fri Mar 22 18:04:52 2019 +0100
+++ b/Admin/components/bundled-windows	Fri Mar 22 19:14:39 2019 +0100
@@ -1,3 +1,3 @@
 #additional components to be bundled for release
-cygwin-20190320
+cygwin-20190322
 windows_app-20181006

--- a/Admin/components/components.sha1	Fri Mar 22 18:04:52 2019 +0100
+++ b/Admin/components/components.sha1	Fri Mar 22 19:14:39 2019 +0100
@@ -48,6 +48,7 @@
 c22048912b010a5a0b4f2a3eb4d318d6953761e4  cygwin-20170930.tar.gz
 5a3919e665947b820fd7f57787280c7512be3782  cygwin-20180604.tar.gz
 2aa049170e8088de59bd70eed8220f552093932d  cygwin-20190320.tar.gz
+fb898e263fcf6f847d97f564fe49ea0760bb453f  cygwin-20190322.tar.gz
 0fe549949a025d65d52d6deca30554de8fca3b6e  e-1.5.tar.gz
 2e293256a134eb8e5b1a283361b15eb812fbfbf1  e-1.6-1.tar.gz
 e1919e72416cbd7ac8de5455caba8901acc7b44d  e-1.6-2.tar.gz

--- a/src/Pure/Admin/build_cygwin.scala	Fri Mar 22 18:04:52 2019 +0100
+++ b/src/Pure/Admin/build_cygwin.scala	Fri Mar 22 19:14:39 2019 +0100
@@ -12,7 +12,7 @@
   val default_mirror: String = "https://isabelle.sketis.net/cygwin_2019"
 
   val packages: List[String] =
-    List("curl", "nano", "perl", "perl-libwww-perl", "rlwrap", "unzip")
+    List("curl", "libgmp-devel", "nano", "perl", "perl-libwww-perl", "rlwrap", "unzip")
 
   def build_cygwin(progress: Progress,
     mirror: String = default_mirror,