Add Powershell equivalent to boostrap.sh

Directly port boostrap.sh to Powershell to make things slightly nicer
for Windows devs.

Author: liujimj

bootstrap.ps1

@@ -0,0 +1,28 @@
+$ScriptDir = Split-Path $script:MyInvocation.MyCommand.Path
+$DataDir = "$ScriptDir/fireplace/cards/data"
+$HsdataDir = "$ScriptDir/hs-data"
+$HsdataUrl = "https://github.com/HearthSim/hs-data.git"
+
+# check python version
+$PyMajor = $(python -c 'import sys; print(sys.version_info[0])')
+$PyMinor = $(python -c 'import sys; print(sys.version_info[1])')
+
+if ($PyMajor -lt 3) {
+	Throw "ERROR: Python 3 and above is required to run Fireplace."
+}
+
+if ($PyMinor -lt 4) {
+	Write-Error "WARNING: Python versions older than 3.4 are known to have issues."
+}
+
+Write-Output "Fetching data files from $HsdataUrl"
+if (!(Test-Path $HsdataDir)) {
+	git clone --depth=1 $HsdataUrl $HsdataDir
+} else {
+	git -C $HsdataDir fetch | Write-Output
+	if ($?) {
+		git -C $HsdataDir reset --hard origin/master | Write-Output
+	}
+}
+
+python "$DataDir/__init__.py" $HsdataDir "$DataDir/CardDefs.xml"