modify cmake to build nc

- modify structure of CMakeLists.txt under apps/
  * move apps/CMakeLists.txt to apps/openssl/ since this is for openssl build
  * create new apps/nc/CMakeLists.txt for nc build
  * modify apps/CMakeLists.txt just add_subdirectory()

- add checking and compile of arc4random_uniform()

- add installing man files, openssl.1 and nc.1

apps/openssl/Makefile.am

@@ -89,6 +89,7 @@ noinst_HEADERS += timeouts.h
 EXTRA_DIST = cert.pem
 EXTRA_DIST += openssl.cnf
 EXTRA_DIST += x509v3.cnf
+EXTRA_DIST += CMakeLists.txt
 
 install-exec-hook:
 	@if [ "@OPENSSLDIR@x" != "x" ]; then \