Build pre-hook, altNames, uInt, getType() calls, add zlib test

Fix subdir header, static lib name, [u]int[\d]+

tests/zlib.nim

@@ -0,0 +1,68 @@
+import os, strutils
+
+import nimterop/[build, cimport]
+
+const
+  baseDir = currentSourcePath.parentDir()/"build"/"zlib"
+
+static:
+  cDebug()
+
+proc zlibPreBuild(outdir, path: string) =
+  let
+    mf = outdir / "Makefile"
+  if mf.fileExists():
+    # Delete default Makefile
+    if mf.readFile().contains("configure first"):
+      mf.rmFile()
+      when defined(windows):
+        # Fix static lib name on Windows
+        setCmakeLibName(outdir, "zlibstatic", prefix = "lib", oname = "zlib", suffix = ".a")
+
+getHeader(
+  "zlib.h",
+  giturl = "https://github.com/madler/zlib",
+  dlurl = "http://zlib.net/zlib-$1.tar.gz",
+  outdir = baseDir,
+  altNames = "z"
+)
+
+cPlugin:
+  import regex, strutils
+
+  proc onSymbol*(sym: var Symbol) {.exportc, dynlib.} =
+    sym.name = sym.name.replace(re"_[_]+", "_").strip(chars = {'_'})
+
+cOverride:
+  type
+    voidpf = ptr object
+    voidpc = ptr object
+    voidp = ptr object
+    uLongf = culong
+    z_size_t = culong
+    z_crc_t = culong
+    alloc_func* {.importc.} = proc(opaque: voidpf, items, size: uint) {.cdecl.}
+    Bytef {.importc.} = object
+  
+  when defined(posix):
+    type
+      pthread_mutex_s = object
+      pthread_cond_s = object
+      pthread_rwlock_arch_t = object
+      extension = object
+      fd_set = object
+
+when defined(posix):
+  static:
+    cSkipSymbol(@["u_int8_t", "u_int16_t", "u_int32_t", "u_int64_t"])
+
+when defined(zlibGit) or defined(zlibDL):
+  when dirExists(baseDir / "build"):
+    cIncludeDir(baseDir / "build")
+
+when not defined(zlibStatic):
+  cImport(zlibPath, recurse = true, dynlib = "zlibLPath")
+else:
+  cImport(zlibPath, recurse = true)
+
+echo "zlib version = " & $zlibVersion()